Version 1.0
March 2016
Dave Smith Instruments LLC
1527 Stockton Street, 3rd Floor
San Francisco, CA 94133
USA
©2016 Dave Smith Instruments LLC www.davesmithinstruments.com
This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference and (2) this device must accept any interference received, including interference that may cause undesired operation.
This Class B digital apparatus meets all requirements of the Canadian
Interference-Causing Equipment Regulations.
Cet appareil numerique de la classe B respecte toutes les exigences du
Reglement sur le materiel brouilleur du Canada.
For Technical Support, email: [email protected]
A Few Words of Thanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
Getting Started . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Sound Banks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Selecting Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Editing Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Comparing an Edited Program to its Original State . . . . . . . . . . . . . . 3
Creating a Program from Scratch . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Live Panel Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Saving a Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Canceling Save . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Moving to the Next Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Global Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Globals - Top Row . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Globals - Bottom Row . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Oscillators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Oscillator Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Detune . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Mixer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Filter Envelope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Changing the Filter Envelope’s Response Curve . . . . . . . . . . . . . . . 24
Loudness Envelope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Effects Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Distortion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Low Frequency Oscillators . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
X-Mod . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
X-Mod Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Arpeggiator Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
Sequencer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
Programming the Sequencer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Sequencer Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Portamento . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
Unison . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
Using Chord Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Write . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
Canceling Save . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Comparing Before You Save . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Globals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
Pitch and Mod Wheels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55
Pitch Wheel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Modulation Wheel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Aftertouch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56
Exporting Programs and Banks . . . . . . . . . . . . . . . . . . . . . . . . .59
Calibrating the OB-6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
How and When to Calibrate the Oscillators and Filters . . . . . . . . . . 60
Calibrating the Pitch and Mod Wheels . . . . . . . . . . . . . . . . . . . . . . . 61
Resetting the Global Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Using USB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62
Appendix A: Alternative Tunings . . . . . . . . . . . . . . . . . . . . . . . .63
Appendix B: Troubleshooting and Support . . . . . . . . . . . . . . .67
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Contacting Technical Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Warranty Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Appendix C: MIDI Implementation . . . . . . . . . . . . . . . . . . . . . . .71
MIDI Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
NRPN Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Control NRPN Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Sysex Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Packed Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Sound Design
Cyan Assiter-Clark, Daniel Davis, Peter Dyer, Peter Gorges, Tim Koon, Kurt
Kurasaki, Kevin Lamb, Peter Mahr, Cord Mueller, Drew Neumann, Bob Oxley,
Robert Rich, Matia Simovich, James Terris, Mitch Thomas, Taiho Yamada,
Lorenz Rhode
The DSI Crew
Fabien Cesari, Bob Coover, Carson Day, Chris Hector, Tony Karavidas, Mark Kono,
Justin Labreque, Andy Lambert, Andrew McGowan, Joanne McGowan, Tracy Wadley, and Mark Wilcox.
Special thanks to Tom Oberheim. Thanks also to Robert Rich for the alternative tunings content.
Thank you for purchasing the OB-6. It’s an awesome-sounding synthesizer and we’re very proud of it, and I’m very proud to have been able to co-create it with my old friend, Tom Oberheim.
I’ve known Tom since the late 1970’s when we both shared the heady experience of creating and selling some of the very fi rst polyphonic synthesizers through our respective companies, Sequential Circuits and Oberheim Electronics. Back in those days, people were typically in either the Prophet or the Oberheim camp, and though we were competitors, we were always
friendly
competitors, and have remained good friends ever since.
Now, many years later, with the analog synth revival, Tom and I are again making the instruments that we love. After I reacquired the Sequential brand and released the Prophet-6 — and saw how much people liked it — the DSI gang and
I thought it would be fun to work with Tom to help bring back his classic SEMbased polyphonic sound in a modern format. So we did. And the result is the very synth that you’ve just unboxed.
The OB-6 takes the best qualities of Tom’s classic SEM-based synths and adds some nice touches that the originals never had, such as stereo outputs, velocity and aftertouch sensitivity, dual digital effects, a polyphonic step sequencer, an arpeggiator, and of course, MIDI. The result is a modern classic: Pure vintage analog tone with the reliability of a state-of-the-art, modern instrument.
Working together to bring you the OB-6 has been a real pleasure. We hope you enjoy it and make some great music with it!
Cheers,
The OB-6 is a six-voice, polyphonic analog synthesizer with voltagecontrolled oscillators, filters, and amplifiers. It was designed to provide all of the warmth, punch, and presence of a classic, SEM-based Tom
Oberheim synthesizer, with the added convenience and stability of a stateof-the-art, modern instrument.
All of the sound-shaping controls of the OB-6 are accessible on its front panel, packing a tremendous amount of power and versatility into a compact, easy-to-use format.
Each of the OB-6’s parameters are explained in later sections of this manual. But don’t hesitate to dive right in and start turning knobs and pressing buttons before you begin reading. You can always get back to where you started, even if you have no idea what you’re doing. So start exploring and keep your ears and mind open!
AFTERTOUCH
AMOUNT
VCO 1 VCO 2
LFO AMT LOUDNESS
FILTR FREQ FILTR MODE
TRANSPOSE
0
PHONES
MODULATION
X-MOD
FILTER ENV VCO 2
VCO 1
PW 1
FILTR FREQ FILTR MODE
WHL RANGE
SHAPE 1
HOLD
LEFT RIGHT
FREQUENCY
LFO SYNC
LFO
SHAPE
INITIAL AMT
SINE
SAWTOOTH
REV SAW
SQUARE
RANDOM
VCO 1 VCO 2 PULSE WIDTH
AMP
2
FILTR FREQ FILTR MODE
TAP TEMPO BPM
PULSE WIDTH
RATE PORTAMENTO KEY MODE DETUNE UNISON
CLOCK
VALUE
VCO 1
FREQUENCY SYNC
OSCILLATORS
FREQUENCY
VCO 2
DETUNE
LP FILTER VOLUME SUSTAIN SEQUENCER
ON/OFF
MIDI THRU MIDI OUT
ARPEGGIATOR
OCTAVES MODE
2
3
LOW FREQ VCO 1
MIXER
VCO 2
MIDI IN USB
SEQUENCER
RECORD PLAY
FILTER
FREQUENCY RESONANCE
ON/OFF EFFECT TYPE
EFFECTS
MIX CLK SYNC 2
ATTACK
A B
DECAY
ENVELOPES
FILTER ENVELOPE
SUSTAIN RELEASE
VELOCITY
AMOUNT
1
OUTPUT
PAN SPREAD PRGM VOL
PULSE WIDTH KEYBOARD
Decrement
BANK BANK PROGRAM
Increment
TENS
SUB OCTAVE NOISE NOTCH BP TRACK ATTACK DECAY SUSTAIN RELEASE
LP HP
Transpose
Local Ctrl
Master Tune MIDI Channel
Seq Jack Pot Mode
MIDI Clock
Sustain +/-
Clock Port
Alt Tuning
VELOCITY
HALF FULL
Param Xmit Param Rcv
LOUDNESS ENVELOPE
MIDI Control MIDI SysEx
Vel Response AT Response Stereo/Mono Pgm Dump
MIDI Out
WRITE
AMOUNT
GLOBALS
MASTER VOLUME
MANUAL
SELECT SELECT 0 1 2 3 4 5 6 7 8 9
PITCH MOD
OB-6 front panel
OB-6 Operation Manual
Getting Started 1
Sound Banks
The OB-6 contains a total of 1000 programs. 500 are permanent and
500 can be overwritten. Banks 0-4 are User Banks that can be overwritten. Banks 5-9 are Factory Banks that are permanent. You can edit the programs of either bank, but you can only save them to Banks 0-4. As shipped from the factory, presets 000-499 are identical to 500-999.
Decrement
BANK BANK PROGRAM
Increment
TENS
Transpose
Local Ctrl
Master Tune MIDI Channel
Seq Jack Pot Mode
MIDI Clock
Sustain +/-
Clock Port
Alt Tuning
Param Xmit Param Rcv MIDI Control MIDI SysEx
Vel Response AT Response Stereo/Mono Pgm Dump
MIDI Out
SELECT SELECT
Program bank, tens, and number selectors
0 1 2 3 4 5
Selecting Programs
Use the bank
, tens
, and program selector buttons to select and recall programs.
To choose a program:
1. Press a program selector
button (0-9) to specify the “ones” digit of the program.
2. Hold down the tens button then press a program selector
button (0-9) to specify the “tens” digit of the program.
3. Hold down the bank button then press a program selector
button (0-9) to specify the “hundreds” bank of the program.
To choose program 123, for example:
1. Hold bank and press 1. Then release the bank
button.
2. Hold tens and press 2. Then release the tens
button.
3. Press program selector
button 3.
6 7 8 9
2
Holding down the decrement
button and pressing the increment
button advances the program number by 1 value. Conversely, holding down the increment button and pressing the decrement
button decrements the program number by 1 value.
This is especially useful for going between Tens, as you can wrap around to the next set.
Getting Started
Dave Smith Instruments
It’s not always necessary to enter all 3 digits of a program number to recall it.
For example:
• If the current program is 100 and you want to recall program 101, simply press “1.”
• If the current program is 100 and you want to recall program 110, hold down the tens
button and press “1.”
• If the current program is 100 and you want to recall program 115, hold down the tens
button and press “1.” Then release the tens
button and press “5.”
Pressing the globals
button three times in a row saves the current program as the default program that appears when you turn on the OB-6.
Editing Programs
Because all of the sound-shaping controls of the OB-6 appear on its front panel, editing an existing program is simple: just turn a knob and listen to its effect. Keep turning knobs and pressing buttons and if you like what you’ve created, save the program. (See “Saving a Program” on page 5.)
The rotary controls on the front panel are a mixture of “endless” rotary encoders and potentiometers or “pots.” You can choose between three different modes that determine how the synth reacts when parameters are edited with a pot. For details, see “Pot Mode” on page 13.
Comparing an Edited Program to its Original State
When editing a program, it’s often useful to compare its edited state to its original state to evaluate your edits. Alternatively, before saving a program to a new location you may want to check the program in the target location before you overwrite it.
To compare an edited program to a saved version:
1. Edit a program.
2. Press the write
button. It starts flashing.
OB-6 Operation Manual
Getting Started 3
3. Press the global
button. Both LEDs on the button light up, indicating compare
mode.
4. Play the keyboard to hear the saved version of the sound.
5. To disable the compare function and return to the edited sound, turn off the global
button. Programs can’t be written while in compare mode.
6. If you want to save the edited sound, the write
button is still flashing and ready to save, so enter a location with the program selector buttons. The sound is saved.
7. Alternatively, if you want to cancel saving and continue editing, press the write
button. It stops flashing and saving is canceled.
When you’re editing a preset, the OB-6 has a convenient way of indicating the programmed (saved) value for any knob parameter: Whenever you turn a knob and reach the saved value of the parameter, an LED dot in the main OB-6 display will illuminate.
Creating a Program from Scratch
An existing program can be very useful as a jumping off point for new sounds. But it’s also useful (and educational) to create a new sound from scratch. The OB-6 makes this easy by providing a “Basic Preset” that you can quickly recall at any time. This preset is very simple, with a single oscillator as its basis.
To recall the Basic Preset:
1. Hold down the manual
button.
2. Press the write
button.
4 Getting Started
Dave Smith Instruments
Live Panel Mode
The OB-6 also features a “live panel” mode in which its sound switches to the current settings of its knobs and buttons. In other words, the current preset is ignored and what you see on the front panel is what you hear. This is a great mode for learning, experimentation, and instant gratification.
To enter live panel mode:
• Press the manual
button to toggle it on. Note that you can’t change programs or banks with manual
on.
To return to preset mode:
• Press the manual
button again to toggle it off.
MANUAL
Toggling on the manual
button enables “live panel” mode
Be aware when entering live panel mode that the current settings of the OB-6 knobs and switches may be such that no sound is produced. This could be because the Mixer levels are all set to zero, or some other reason. See
Appendix B: Troubleshooting and Support
for a checklist that can help you identify the cause.
Saving a Program
If you’ve created a sound that you like, you’ll probably want to save it.
Saving a program overwrites a previously saved program. Sound designers often save many incremental versions of a program as they continue to refine it. These intermediate versions often make good jumping off points for new sounds.
To save a program to the same preset location:
1. Press the write
button. Its LED begins blinking.
2. Press a program selector
button (0-9) to specify the “ones” digit of the program.
3. The write
button LED stops blinking and the program is saved.
OB-6 Operation Manual
Getting Started 5
Be careful when write
is enabled. You can change banks and tens without executing write
, but once you press a program selector
button (0-9) for the “ones” digit, the write
command is executed and the program at that location is overwritten.
To save a program to a different bank location:
1. Press the write
button. Its LED begins blinking.
2. Hold down the bank button then press a program selector
button to specify the “hundreds” bank of the program. You can only save to
Banks 0-4.
3. Hold down the tens button then press a program selector
button (0-9) to specify the “tens” digit of the program.
4. Press a program selector
button (0-9) to specify the “ones” digit of the program.
5. The write
button LED stops blinking and the program is saved.
Canceling Save
Sometimes you may want to cancel saving a program before you commit.
To cancel the Save process before you commit:
• If the write
button LED is flashing, press it again. The LED stops flashing and saving is canceled. You can return to editing if you want.
6 Getting Started
Dave Smith Instruments
Comparing Before You Save
Before saving a program to a new location, it’s a good idea to listen to the program in the target location to make sure you really want to overwrite it.
To evaluate a program before you overwrite it:
1. Get ready to save by pressing the write
button. It starts flashing.
2. Press the global
button. Both LEDs on the button light up, indicating compare
mode.
3. Use the program buttons to navigate to the sound you want to compare and play the keyboard to hear the sound.
4. To disable the compare function and go back to the edited sound, turn off the global
button. Programs can’t be written while in compare mode.
5. If you want to save the edited sound, the write
button is still flashing and ready to save, so enter a location with the program buttons. The sound is saved.
6. Alternatively, if you want to cancel saving and continue editing, press the write
button. It stops flashing and saving is canceled.
Moving to the Next Level
Before you start exploring the sound creation capabilities of the OB-6 we’d like to point you toward a few things that will help you tailor the instrument to your needs.
First, check out the
Global Settings
section of this manual. Read about
Pot Modes and determine which works best for you when you’re editing sounds. You’ll also find information about MIDI setup. Read this to more effectively integrate the OB-6 into your MIDI rig. To get the most out of the OB-6’s live performance capabilities, read up on using a footswitch or expression pedal.
And finally, be on the lookout for tips and notes scattered throughout this manual to gain a better working knowledge of the OB-6. The better you know it, the more you’ll get out of it. We wish you many hours of musical exploration!
OB-6 Operation Manual
Getting Started 7
1 2 3
1 . AC Power Connector
—
Accepts a standard, grounded IEC power cord. Operates over a range of 100 to 240 volts and 50 to 60 Hz.
2 . USB
—
For bidirectional MIDI communication with a computer. The
OB-6 is a Class Compliant USB device and does not require additional drivers when used with Mac OS or Windows. See
Using USB
on page
62 for more information.
3 . MIDI In, Out, and Thru
—
Standard 5-pin MIDI DIN connectors.
4 . Footswitch-Sequence
—
Accepts a momentary, normally open or normally closed footswitch to turn the sequencer or arpeggiator on and off. Alternatively, an audio signal connected to this jack can be used to either control sequencer/arpeggiator playback, or to gate the filter and loudness envelopes while notes are held. See “Seq Jack” on page 13 for more information about choosing the appropriate mode for these behaviors.
4 5 6 7
Audio signals used to drive the arpeggiator/sequencer should not exceed 5 volts peak-to-peak.
5 . Footswitch-Sustain
—
Accepts a momentary, normally open or normally closed footswitch to control sustain. See Sustain” on page
14 for more information.
8 Connections
Dave Smith Instruments
8 9
1 2 3 4 5 6 7 8 9
6 . Expression Pedal-Volume
—
Accepts a standard expression pedal that has a variable resistor on a TRS (tip-ring-sleeve) ¼ inch phone plug.
Once connected, you can use the pedal to control volume to add expressiveness and dynamics to live performance.
7 . Expression Pedal- Filter
—
Accepts a standard expression pedal that has a variable resistor on a TRS (tip-ring-sleeve) ¼ inch phone plug.
Once connected, you can use the pedal to control the cutoff frequency of the filter to add expressiveness to live performance.
8 . Audio Outputs
—
Unbalanced, ¼ inch audio outputs. The OB-6 sounds great in stereo, but can be switched to mono if needed. See
“Mono/Stereo” in
Global Settings
on page 14.
9 . Headphones
—
A ¼ inch stereo headphone jack. Headphone volume is controlled by the master volume
knob on the front panel.
OB-6 Operation Manual
Connections 9
Global settings are parameters that affect all programs. These include settings such as Master Tune, MIDI Channel, MIDI Clock, and others.
Global parameters are printed above the numeric program selector switches (0 - 9). Use the Globals switch to choose between the two sets.
The red LED indicates that the upper row is active. The yellow LED indicates that the lower row is active
GLOBALS
The Globals button
Transpose
Local Ctrl
Master Tune MIDI Channel
Seq Jack Pot Mode
MIDI Clock
Sustain +/-
Clock Port
Alt Tuning
Param Xmit Param Rcv MIDI Control MIDI SysEx
Vel Response AT Response Stereo/Mono Pgm Dump
MIDI Out
0
Globals 0-4
1 2 3 4
Transpose
Local Ctrl
Master Tune MIDI Channel
Seq Jack Pot Mode
MIDI Clock
Sustain +/-
Clock Port
Alt Tuning
Param Xmit Param Rcv MIDI Control MIDI SysEx
Vel Response AT Response Stereo/Mono Pgm Dump
MIDI Out
5 6 7 8 9
0 1 2 3 4 5 6 7
Globals 5-9
Decrement
BANK BANK PROGRAM
Increment
TENS
8 9
SELECT SELECT
Use the Bank and Tens buttons to scroll forward and backward, respectively, through parameter settings
10 Global Settings
Dave Smith Instruments
To set a Global parameter:
1. Press the globals button. Pressing it once activates the upper set of parameters. Pressing it a second time enables the lower set of parameters.
2. Press the program selector button (0 - 9) that corresponds to the desired parameter. The parameters are printed above each switch.
3. Use the bank
and tens
buttons as decrement and increment buttons to step through available settings.
4. Once you’ve chosen the desired setting, press the globals
button again to exit.
Globals - Top Row
0 . Transpose:
-12
…
12
—
Master Transpose control, 0 is centered. Steps in semitones up to one octave up (+12) or down (-12).
1 . Master Tune:
-50
…
50
—
Master Fine Tune control; 0 centered. Steps in cents as much as a quarter-tone up (+50) or down (-50).
2 . MIDI Channel:
All
,
1
…
16
—
Selects which MIDI channel to send and receive data, 1 to 16. all
receives on all 16 channels.
3 . MIDI Clock:
messages:
Sets the OB-6’s ability to send and receive MIDI clock
•
Off
: MIDI Clock is neither sent nor received
•
Out
: MIDI Clock is sent, but not received
•
In
: MIDI Clock is received, but not sent
• Slave Thru ( i-0
): MIDI Clock is received and passed to MIDI Out
• In, No Start/Stop ( n55
): Receives MIDI Clock but does not respond to
MIDI Start or Stop commands.
When set to in
or slave thru
, if no MIDI clock is present at the selected input, the arpeggiator and sequencer will not function.
OB-6 Operation Manual
Global Settings 11
4 . Clock Port:
MID
,
USB
—
Sets the ports, MIDI or USB, by which MIDI clock signals are received.
5 . Param Xmit:
Off
,
CC
,
NR
—
Changes to the values of front panel controls are transmitted via MIDI as Continuous Controllers (
CC
) or Nonregistered Parameter Number (
NR
). Transmission of parameters can also be turned off. You could, for example, turn the filter frequency
knob on the
OB-6 and have it affect the cutoff frequency of another synthesizer. For a list of OB-6 CCs and NRPNs, see Appendix D.
NRPNs are the preferred method of parameter transmission, since they cover the complete range of all parameters, while CCs are limited to a range of 128.
6 . Param Rcv:
Off
,
CC
,
NR
—
Sets the method by which parameter changes are received via MIDI. As with transmission, NRPNs are the preferred method.
7 . MIDI Control:
Off
,
On
—
When On, the synth will respond to MIDI controllers, including Pitch Wheel, Mod Wheel, Pedal, Volume.
8 . MIDI Sysex:
MID
,
USB
—
When set to MIDI (
MID
) it will receive and transmit them using the MIDI ports/cables When set to USB it will receive and transmit them using the USB port/cable. MIDI SysEx messages are used when sending and receiving a variety of data including, programs, alternative tunings, system updates, and more.
9 . MIDI Out:
MID
,
USB
—
Sets the port by which MIDI data will be transmitted (MIDI or USB).
Globals - Bottom Row
0 . Local Control:
Off
,
On
—
When on (the default), the keyboard and front panel controls directly affect the OB-6. When off, the controls are transmitted via MIDI but do not directly affect the “local” synth (that is, the OB-6). This is primarily useful for avoiding MIDI data loops that can occur with some external sequencers.
12 Global Settings
Dave Smith Instruments
1 . Seq Jack:
NOR
,
Tri
,
Gat
,
T-g
(Normal, Trigger, Gate, T-G)—
Selects the mode for signals received on the rear-panel Sequencer jack.
• With normal
selected, a footswitch will start sequencer playback.
• With trig
selected, an audio signal connected to the sequencer
jack will step the sequencer when the sequencer’s play
button is on.
• With gate
selected, an audio signal connected to the sequencer jack will trigger and gate the envelopes while you hold a note or chord. Additionally, turning on the sequencer or arpeggiator will add sequencer or arpeggiator playback—but controlled by the OB-6’s clock bpm
and value
settings and not the audio trigger.
• With t
g
( trigger
+ gate
) selected, an audio signal connected to the sequencer
jack will trigger and gate the envelopes while you hold a note or chord. Additionally, pressing the sequencer’s play
button will also add synchronized sequencer playback.
For best results when triggering the sequencer with an audio signal, use a loud signal with a sharp attack/decay and little or no sustain.
2 . Pot Mode:
Rel
,
Pas
,
Jup
(Relative, Passthru, Jump)—
The rotary controls on the front panel are a mixture of “endless” rotary encoders and potentiometers or “pots.” The pots are identifiable by their lined knobs and the fact that they have about 300° of travel. There are three pot modes to determine how the synth reacts when the programmable parameters are edited.
(Master volume is not programmable, so these modes don’t apply.)
In
Relative
mode, changes are relative to the stored setting. In Relative mode, the full value range is not available until either the minimum or maximum value and the respective lower or upper limit of the pot’s travel is reached. For example, the resonance
parameter has an internal value range of 0 to 127. Let’s say the physical position of the resonance
pot is the equivalent to a value of 100. If you switch to a program that has a stored Resonance setting of 63 and turn the pot all the way up, it will only go to 90. To get to the maximum value of 127, you first have to turn down until the value is at the other extreme and the pot is at the limit of its travel (in this case, 0 and fully counter-clockwise, respectively).
In
Passthru
mode, turning the pot has no effect until after the edited value equals the preset value (that is, until the edited value “passes through” the stored value).
OB-6 Operation Manual
Global Settings 13
Jump
mode uses an absolute value based upon the position of the pot when edited: turn a pot and the value jumps immediately from the stored value to the edited value.
3 . Sustain +/- :
Nor
,
Rev
, n-r
, r-n
(Normally Open, Normally Closed,
Sustain Normally Open/Sequencer Normally Closed, Sustain Normally
Closed/Sequencer Normally Open)—
The Sustain pedal polarity parameter affects both the sustain pedal and sequencer jack input ports. There are two types of momentary footswitches, normally open and normally closed. Either type can be used with the OB-6. Not sure which type you have? If the behavior of the footswitch is the opposite of what is expected — that is, down is off and up is on — changing this setting will correct that.
4 . Alt Tuning:
Nor
,
1
…
16
(Normal, 1…16)—
Selects one of the OB-6’s builtin tunings. Set to normal
, the tuning is standard, chromatic tuning. Choosing
1 through 16 selects an alternative, non-chromatic, non-Western scale that can be used to emulate ethnic instruments or in other creative ways.
See “Appendix A: Alternative Tunings” on page 63 for a description of each tuning. Additional tunings can be imported into the OB-6 as a SysEx message. For more information, see Appendix A.
5 . Vel Response:
0-3 (Curve 0, Curve 1, Curve 2, Curve 3)—
Sets one of four velocity curves to adjust the keyboard’s velocity response to your playing style.
6 . AT Response:
0-3 (Curve 0, Curve 1, Curve 2, Curve 3)—
Sets one of four pressure curves to adjust the keyboard’s aftertouch response to your playing style.
7 . Stereo/Mono:
Ste
,
Mon
(Stereo, Mono)—
The OB-6 defaults to stereo operation. When set to Mono, this parameter defeats all pan settings and modulation, effectively making each of the outputs a mono output.
8 . Pgm Dump:
Prg
,
Ten
,
Ban
, usr
,
All
(
Program, Tens, Bank, User
Banks, All)—
Transmits the current program, ten programs from the currently selected bank and tens location, the current bank, all user banks (0-4), or all banks (both user and factory) in SysEx format via the selected MIDI port. (See: “MIDI Sysex.”) Dumped programs will load back into the same bank and program location in memory when received by the OB-6 via MIDI.
14 Global Settings
Dave Smith Instruments
Oscillators provide the raw building blocks of the OB-6’s sound by producing
waveforms
, each of which has its own inherent sound character based on its harmonic content. The OB-6 has two oscillators, plus a sub oscillator and a noise generator per voice. Level controls for each of these are located in the Mixer section.
Oscillator 1 is capable of generating sawtooth, and variable-width pulse waves. Oscillator 2 generates triangle, sawtooth, and variable-width pulse waves. These waveshapes are continuously variable and smoothly transition from one shape to the next as you turn the shape
knob. This provides a variety of “in-between” waveshapes.
The oscillators on the OB-6 are extremely stable. To emulate the random pitch drift and oscillator instability of vintage instruments, use the detune
parameter (next to the unison
button) to dial in as little or as much drift as you like.
FREQUENCY
VCO 1
SYNC
OSCILLATORS
FREQUENCY
VCO 2
DETUNE LOW FREQ
PULSE WIDTH PULSE WIDTH KEYBOARD
Oscillators 1 and 2
Oscillator 1 can be hard-synced to Oscillator 2 for complex, harmonically-rich sounds when modulated.
Oscillator 2 features a detune
knob for detuning and thickening sounds, a low freq
switch that allows it to function as an LFO for modulation purposes, and a keyboard
switch that disables keyboard control over its pitch (useful when used as an LFO, or for drones and other effects).
OB-6 Operation Manual
Oscillators 15
Oscillator Parameters
Frequency:
Sets the base oscillator frequency over a 9-octave range from
16 Hz to 8KHz (when used with the Transpose buttons). Adjustment is in semitones.
The global Master Tune settings affect the pitch of all oscillators. See
“Globals -
Top Row” on page 11
for more information.
Detune:
Fine tune control with a range of a quartertone up or down. The
12 o’clock position is centered. Steps are in cents (50 cents = 1/2 semitone).
Shape:
Sawtooth, Pulse (and Triangle on Osc 2) —
Used to select the waveshape generated by the oscillator. Waveshapes are continuously variable and smoothly transition from one shape to the next as you turn the shape
knob. This provides a variety of “in-between” waveshapes.
Pulse Width:
Changes the width of the pulse wave from a square wave when the pulse width
knob is at center position, to a very narrow pulse wave when the pulse width
knob is full left or right.
Applying pulse width modulation using X-m od
or the low frequency oscillator is a great way to add movement and thickness to a sound, especially when creating pad or string-like sounds.
Sync:
Off, On
—Turns Oscillator 1 hard sync on. Sync forces Oscillator
1 (the slave) to restart its cycle every time Oscillator 2 (the master) starts a cycle. This provides a way to create more complex, harmonically rich shapes from simple waveforms—especially when the frequency of Oscillator 1 is set to a different interval than Oscillator 2.
16 Oscillators
Dave Smith Instruments
Oscillator 1
Oscillator 2
Oscillator 1 synced to
Oscillator 2
Oscillator hard sync
Use X-Mod to sweep the pitch of Oscillator 1 when it is synced to generate the classic, hard-edged sync sound.
Low Frequency:
Off, On
—Turns Oscillator 2 into a low-frequency oscillator, essentially providing another LFO source for modulation using X-Mod. The frequency
, detune
, shape
, and pulse width
controls still apply and will affect the character of any low-frequency modulation applied using Oscillator 2.
Keyboard:
Off, On
—When off, the Oscillator 2 ignores the keyboard and note data received via MIDI and plays at its base frequency setting.
Oscillator 2 pitch can still be affected by modulation from other sources when in this mode.
OB-6 Operation Manual
Oscillators 17
Detune (next to the unison
button) adds randomized detuning to the oscillators to emulate the tuning instability of vintage analog oscillators.
This tuning instability is a big part of what made vintage instruments sound characteristically warm and fat.
Because the OB-6 oscillators are extremely stable, small amounts of detune
can help impart a very vintage tone to what is otherwise a very stable, modern instrument. detune
amount is adjustable from subtle to wildly out of tune.
When unison
is enabled, detune
detunes the unison voices by a fixed amount. Using the pan spread
feature, if an odd number of voices is stacked, one of the voices is placed in the center of the stereo field with the other voices spread right and left. The higher the pan spread setting, the wider the stereo spread in unison.
DETUNE UNISON
The detune
knob
The global Master Tune settings affect the pitch of all oscillators. See
“Globals -
Top Row” on page 11
for more information.
18 Detune
Dave Smith Instruments
The Mixer section is where you set the levels of the various sound generators on the OB-6. These include VCO 1, VCO 2, Sub Octave (Oscillator
1 sub oscillator) and the white noise generator. You must turn up at least one of these in order to make sound with the OB-6.
Rather than limit the OB-6’s outputs to keep the instrument from clipping, we allow you to adjust levels at various points in its signal path. This gives you the option to “overload” things in interesting ways, if you wish to do so. If not, try reducing the levels of the oscillators in the miXer
section, the env amount
parameter in the Loudness
Envelope, or the resonance
parameter in the filter.
VCO 1
VCO 2
SUB OCTAVE NOISE
The Mixer
VCO 1:
Sets the output level of Oscillator 1.
VCO 2:
Sets the output level of Oscillator 2.
Sub Octave:
Controls the level of a square wave oscillator pitched one octave below Oscillator 1. Adding a sub octave to sounds such as bass are a great way to increase their low-register presence.
Noise:
Sets the output level of the white noise generator.
OB-6 Operation Manual
Mixer 19
The Filter takes the basic, raw sound of the oscillators and noise generator and subtracts frequencies, changing the harmonic content and character of their sound. This change can be varied over time using the Filter
Envelope to produce more dynamic, animated timbres.
The OB-6’s filter is a 2-pole, 12 dB per octave, analog, state-variable filter with low-pass, notch, high-pass, and band-pass modes.
The filter mode knob sets the filter’s mode of operation. It transitions smoothly from low-pass to notch to high-pass operation, allowing a blending of these modes. Band-pass operation is selected with the BP switch. Each filter mode has its own characteristic sound and function:
• Low-pass: passes frequencies below the cutoff frequency
• Notch: removes frequencies in a notch centered around the cutoff frequency
• High-pass: passes frequencies above the cutoff frequency
• Bandpass: passes a band of frequencies centered around the cutoff frequency
Band-pass mode is selectable only through the bp
on/off switch. However, you can actually smoothly transition between normal and band-pass operation by choosing norm
bp
as a X-Mod destination in the mod matrix.
FREQUENCY RESONANCE
NOTCH
LP
The OB-6 Filter
HP
BP TRACK
HALF FULL
20 Filter
Dave Smith Instruments
Frequency:
Sets the filter’s cutoff frequency. In Low-Pass mode, frequencies are reduced from the top down — cutting the high frequencies and passing the low, hence the name “low-pass.” In High-Pass mode, frequencies are reduced from the bottom up — cutting the low frequencies and passing the high, hence the name “high-pass.” In Notch mode, frequencies are removed in a notch centered around the cutoff frequency.
In Bandpass mode, a band of frequencies are passed through the filter centered around the cutoff frequency — while frequencies on either side of that band are removed.
Resonance:
Emphasizes a narrow band of frequencies around the cutoff frequency. Unlike low-pass filters on some synthesizers, the OB-6 Low-
Pass filter does not self oscillate. This is faithful to the original Oberheim
SEM design.
High levels of resonance can sometimes cause the OB-6 outputs to clip if its sound generators are also set to high output in the Mixer. Monitor your outputs carefully to ensure optimal, clean signal levels. If you experience signal clipping, try reducing the levels of the oscillators in the miXer
section, the amount
parameter in the
Loudness Envelope, or the resonance
parameter in the filter.
Track:
off, half, full
—Sets the amount of modulation from the keyboard to the filter’s cutoff frequency. Selecting half
or full
means that the higher the note played on the keyboard, the more the filter opens. This is useful for adding brightness to a sound as higher notes are played, which is typically how acoustic instruments behave. If both half
and full are off, keyboard filter tracking is off, meaning that filter frequency is unaffected by playing higher or lower notes on the keyboard.
OB-6 Operation Manual
Filter 21
The OB-6 filter has a dedicated, four-stage envelope generator. The Filter
Envelope is used to shape the harmonic characteristics of a synthesized sound by giving you filtering control over its attack, decay, sustain, and release stages.
This is one of the most important factors in designing a sound. Without an envelope, the filters would be completely static. They would stay open or closed by a fixed amount that wouldn’t change over the duration of a sound. That’s not very interesting to listen to and it’s not how instruments behave in the real world.
In general, sounds produced by an instrument are brighter at their beginning (the attack stage) and grow mellower as they die out (the decay and release stages). In other words, their harmonic content changes over time. This is exactly what the filter envelope is designed to emulate.
ATTACK DECAY
FILTER ENVELOPE
SUSTAIN RELEASE AMOUNT
VELOCITY
Filter Envelope
Time
A typical 4-stage envelope
22 Filter Envelope
Dave Smith Instruments
Attack:
Sets the attack time of the envelope. The higher the setting, the slower the attack time and the longer it takes for the filter to open from the level set with the filter frequency
knob to the level set by the filter envelope amount. Percussive sounds typically have sharp (short) attacks.
Decay:
Sets the decay time of the envelope. After a sound reaches the filter frequency set at its attack stage, decay
controls how quickly the filter then transitions to the cutoff frequency set with the sustain
knob.
The higher the setting, the longer the decay. Percussive sounds, such as synth bass, typically have shorter decays (and a generous amount of lowpass filter resonance).
Sustain:
Sets the filter cutoff frequency for the sustained portion of the sound. The sound will stay at this filter frequency for as long as a note is held on the keyboard.
Release:
Sets the release time of the envelope. This controls how quickly the filter closes after a note is released.
Velocity:
on, off
—When enabled, allows key velocity to influence filter frequency. If the amount
is set to a positive value in low-pass filter mode, the harder you play, the more the filter will open and the brighter the sound will be. Conversely, if the amount
is set to a negative value, the harder you play, the more the filter will close and the less bright the sound will be. This control makes for more touch-sensitive sounds
Amount:
Sets the amount of modulation from the filter envelope to the filter. Higher amounts more dramatically affect the cutoff frequency. This control is bipolar. Positive settings produce standard behavior. Negative settings invert the envelope.
The description of envelope behavior above is true when the amount
parameter is set to a positive value. But since this control is actually bi-polar, it is possible to set a negative amount of modulation. In this case, the envelopes are inverted and their behavior changes. The best way to get a feel for the difference is to experiment with both positive and negative settings of the envelope amount
parameter.
The cutoff frequency setting may limit the effect of the envelope on the filter. For example, in low-pass filter mode , if frequency
is at its highest setting, a positive envelope amount will have no effect on the filter since the filter is already completely open.
OB-6 Operation Manual
Filter Envelope 23
Changing the Filter Envelope’s Response Curve
By default, the envelopes of all synthesizers are designed to have certain type of response curve that is largely dependent on the preference of the designer. In most cases, this can’t be changed. The current preference is that the faster or snappier the envelopes, the better.
However, in the case of the OB-6, there is a hidden feature in the X-Mod section that allows you to modify the responsiveness of the Filter Envelope’s ADSR controls. This opens up a new level of fine adjustment of these controls that is subtle but powerful. Try it and see.
To adjust the responsiveness of the filter envelope:
1. Select a program — such as a synth brass sound — that has a slightly soft but bright attack.
2. Repeatedly play a series of notes or chords on the keyboard, so you can hear the effect of the adjustments as you follow the steps below.
3. In the X-Mod section, enable the filtr freq
as the only destination
(disable all other X-Mod destinations such as vco
1 , shape
1, etc.).
4. In the X-Mod section, turn the filter env
control slightly counterclockwise. Try a setting of about 11 o’clock.
5. Continue to play a series of chords and turn the amount
knob in the filter envelope
section. Try moving it back and forth between 1 o’clock and 3 o’clock.
6. As you do this, compare different settings of the X-Mod filter env control, the Filter Envelope amount
, and different Attack, Decay,
Sustain, and Release settings on the Filter Envelope.
The interaction of these controls is worth exploring for greater flexibility and control of the Filter Envelope.
24 Filter Envelope
Dave Smith Instruments
After passing through the filters, a synthesized sound goes into an analog voltage controlled amplifier or VCA, which controls its overall loudness.
The VCA has a dedicated, four-stage envelope generator.
The Loudness Envelope is used to shape the volume characteristics of a sound over time by giving you control over its attack, decay, sustain, and release stages. Along with the filter envelope, this is one of the most important factors in designing a sound.
Without a loudness envelope, the volume of a sound wouldn’t change over the duration of a note. It would begin immediately, remain at its full volume for the duration of the note, then end immediately when the note was released. Again, that’s not very interesting sonically and it’s not typically how instruments behave in the real world.
To give you a real-world example, the main difference between the sound of the wind and the sound of a snare drum is that they have very different loudness envelopes. Otherwise, they are essentially both white noise. Wind has a relatively slow attack, a long sustain, and a long decay and release. A snare drum has a sharp attack, no sustain, and virtually no decay or release. But again, they are both fundamentally white noise.
ATTACK DECAY SUSTAIN RELEASE
VELOCITY
AMOUNT
LOUDNESS ENVELOPE
Loudness Envelope
Time
A typical four-stage, ADSR envelope shape
OB-6 Operation Manual
Loudness Envelope 25
Attack:
Sets the attack time of the envelope. The higher the setting, the slower the attack time and the longer it takes for a sound to reach its full volume. Pads typically have softer (longer) attacks. Percussive sounds have sharper (shorter) attacks.
Decay:
Sets the decay time of the envelope. After a sound reaches its full volume at its attack stage, decay
controls how quickly the sound transitions to the level set with the sustain
control. The higher the setting, the longer the decay. Percussive sounds, such as synth bass, typically have shorter decays.
Sustain:
Sets the sustain level of the envelope. The higher the setting, the louder the sustained portion of the sound will be. The sound will stay at this level for as long as a note is held on the keyboard.
Release:
Sets the release time of the envelope. This controls how quickly a sound dies out after a note is released.
Amount:
Sets the amount of modulation from the Loudness Envelope to the VCA. In most cases you will probably want to set this fully clockwise for maximum VCA volume. If you experience signal clipping, try reducing the env amount
or the levels of the oscillators in the mixer
section.
To recreate the “gated VCA” effect used on certain classic rock anthems, choose an organ sound, then set the loudness envelope amount to zero, route the LFO square wave to amp with an initial amt
setting of 100% and hold a few chords.
Velocity:
This button enables keyboard velocity to modulate the Loudness Envelope amount. The harder you play, the more the Loudness
Envelope is affected. This makes for more touch-sensitive sounds.
26 Loudness Envelope
Dave Smith Instruments
The OB-6 effects
section allows you to add up to two, 24-bit, 48 kHz digital effects to any sound. Though the OB-6 sounds great on its own, adding a touch of reverb or delay can enhance many sounds with a subtle (or not so subtle) sense of ambience and depth. Other effects such as the chorus and phaser are useful for adding more conspicuous tonal enhancement as well as emulating classic instruments such as string ensembles and so on.
While the effects themselves are digital, the main signal path of the OB-6 is analog. The on
/ off
switch enables and disables both Effect A and
Effect B, using a true bypass, ensuring a pure analog signal path.
Effects settings are saved individually with each program. Time-based effects such as the Delays can be synchronized to the arpeggiator, sequencer, or MIDI clock to produce repeats that occur on the beat.
EFFECTS
MIX CLK SYNC ON/OFF EFFECT TYPE 2
A B
1
The Effects section
Effects are divided into sets A and B. You can choose a single effect from each set. Effect A and B are applied one after another, in series. For this reason, reverb effects are only available as Effect B, since it’s the last stage in the serial effects chain — where reverb is traditionally applied.
Either effect can also be set to “off.”
OB-6 Operation Manual
Effects 27
Effect A:
• Delay 1 (“ bbd
”) - vintage bucket-brigade emulation
• Delay 2 (“ ddl
”) - classic digital delay
• Chorus (“
CHO
”) - vintage chorus
• Flanger 1 (“
FL1
”) vintage flanger, high resonance
• Flanger 2 (“
FL2
”) vintage flanger, no feedback
• Phase Shifter 1 (“
PH1
”) vintage 6-stage phaser, high resonance
• Phase Shifter 2 (“
PH2
”) vintage 6-stage phaser, lower resonance
• Phase Shifter 3 (“
PH3
”) faithful emulation of Tom Oberheim’s original 6-stage phaser
• Ring Modulator (“
Ri n
”) faithful emulation of Tom Oberheim’s original ring modulator design
Effect B:
• Delay 1 (“ bbd
”) - vintage bucket-brigade emulation
• Delay 2 (“ ddl
”) - classic standard digital delay
• Chorus (“
CHO
”) - vintage chorus
• Flanger 1 (“
FL1
”) vintage “through-zero” flanger, high resonance
• Flanger 2 (“
FL2
”) vintage “through-zero” flanger, no feedback
• Phase Shifter 1 (“
PH1
”) vintage 6-stage phaser, high resonance
• Phase Shifter 2 (“
PH2
”) vintage 6-stage phaser, lower resonance
• Phase Shifter 3 (“
PH3
”) faithful emulation of Tom Oberheim’s original 6-stage phaser
• Ring Modulator (“
Ri n
”) faithful emulation of Tom Oberheim’s original ring modulator design
• Reverb 1 (“
HAL
”) - classic hall emulation
• Reverb 2 (“ rOO
”) - classic room emulation
• Reverb 3 (“
PLA
”) - classic plate emulation
• Reverb 4 (“
SPr
”) - vintage guitar-amp-style spring emulation
28 Effects
Dave Smith Instruments
To use Effects:
1. Press the on
/ off
switch to turn on Effects.
2. Press effect
and choose A or B, depending on which you want to apply and configure.
3. Turn the type
knob to select an effect. Names are abbreviated. For instance “bbd” is the bucket-brigade delay. Refer to the list above.
4. Turn the mix
knob to the right to blend in a good amount of the processed signal. You’ll want to be able to clearly hear the effect when you tweak its settings. You can dial it down afterward.
5. Use the parameter 1 and parameter 2 knobs to adjust the effect’s parameters to your taste. See “Effects Parameters” on page 29 for details on the adjustable parameters on each effect type.
6. Finally, adjust the mix
knob to optimize the amount of the effect. Full left is completely dry. Full right is completely wet (a 100% processed signal).
7. Repeat as needed to add a second effect.
Effects Parameters
On/Off:
Turns both effects, A and B, on and off.
The on
/ off
switch uses a true bypass, ensuring a pure analog signal path.
Effect:
A, B
—Selects either effect A or B for editing. Once selected, all adjustments apply to that effect.
Type:
Off
, bbd
, ddl
,
CHO
,
FL1
,
PH1
,
PH2
,
PH3
,
RNG
,
HAL
, rOO
,
PLA
,
SPr
—Selects the effect type.
Mix:
0
...
127
—Sets the balance between the processed (wet) signal and unprocessed (dry) signal. Full left is completely dry. Full right is completely wet.
OB-6 Operation Manual
Effects 29
Clock Sync:
On
,
Off
—When a delay effect is chosen, this enables syncing of the timed delay repeats (feedback) to the Arpeggiator, Sequencer, or MIDI clock. When Sync is on, delay time provides the following values:
8
8t
16d
16
4t
4d
4
8d
Value
1
2d
2
Delay Time
4 beats
3 beats
2 beats
1 beat
1 1/2 beat
1 beat
3/4 of 1 beat
1/2 of 1 beat
1/2 of 1 beat
3/8 of 1 beat
1/4 of 1 beat
Maximum delay time is 1 second. The combination of longer synced delay times with slower tempos can result in delay times that would be greater than 1 second. When that happens, the delay time is divided by 2 until it no longer exceeds the 1 second limit. For example, if the BPM is set to 60 and Delay Time is set to Half, the expected delay time would be 2 seconds. The actual delay time will be 1 second
(i.e. 2 seconds divided by 2).
Parameter 1:
Variable, depending on the effect
—This knob adjusts parameter 1 for the chosen effect. Each effect has two adjustable parameters, which differ depending on the effect.
Parameter 2:
Variable, depending on the effect
—This knob adjusts parameter 2 for the chosen effect. Each effect has two adjustable parameters, which differ depending on the effect.
30 Effects
Dave Smith Instruments
fl2
PH1
PH2
PH3
Rin
Display
bbd ddl cho fl1
HAL rOO
PLA
SPr
Effect Type
bucket-brigade delay digital delay chorus flanger flanger phaser 1 phaser 2 phaser 3 ring modulator hall reverb room reverb plate reverb spring reverb
Parameter 1
delay time delay time rate rate rate rate rate rate modulator frequency time time time decay
Parameter 2
feedback amount feedback amount depth depth depth depth depth depth low-note pitch tracking on/off early reflections early reflections early reflections tone
bbd:
This is a vintage bucket-brigade delay emulation. Bucket-brigade delays were originally a type of analog delay characterized by relatively short delay times and a warmer character than digital delays due to their loss of treble and clarity in the delayed analog signal. Adjustable parameters are delay time and feedback amount.
To recreate a classic bucket-brigade time-shifting effect, try adjusting the time parameter in real time.
ddl:
This is a classic digital delay. Adjustable parameters are delay time and feedback amount.
CHO:
This is a vintage chorus emulation. Use it to thicken and add animation to any sound. Adjustable parameters are rate and depth.
FL1:
This is a vintage flanger emulation. Use it to add a sweeping resonant effect to a sound. This effect has true through zero flanging capability. Adjustable parameters are rate and depth.
OB-6 Operation Manual
Effects 31
FL2:
This is a vintage flanger without a feedback path and is designed to emulate the through zero capability of tape deck flanging. Use it to add a sweeping flanged effect to a sound. Adjustable parameters are rate and depth.
PH1:
This is a vintage phaser emulation with high resonance. Use it to add a deep, sweeping, swirling resonant effect to a sound. Adjustable parameters are rate and depth.
PH2:
This is a vintage phaser emulation with lower resonance. Use it to add a swirling resonant effect to a sound. Adjustable parameters are rate and depth.
PH3:
This is a faithful emulation of Tom Oberheim’s original phaser design. Use it to add a swirling resonant effect to a sound. Adjustable parameters are rate and depth.
rin:
This is a faithful emulation of Tom Oberheim’s original ring modulator design. Use it to add a complex harmonic effect to a sound. Adjustable parameters are the modulation frequency and low note pitch tracking on/off.
The ring modulator’s mode of operation is determined by the setting of Parameter 2, (pitch tracking) which can be set to either on or off. With this parameter off, the ring modulator functions like the original Oberheim unit. In this mode, pitch tracking is off, and Parameter 1 sets the modulation frequency, which remains the same regardless of what note you play on the keyboard. With parameter 2 on, the ring modulator tracks the pitch of the lowest note that you play on the keyboard. In this case the
Parameter 1 sets a ratio between the lowest note that you play and the modulator note
(instead of setting a fixed frequency). The modulation frequency will then change as you change the lowest note that you’re playing, so that the ratio will remain constant between the note that you play and note of the modulator. If you are only playing one note at a time, then the ring modulator will modulate with the same ratio as you play up and down the keyboard.
Set Parameter 2 to the “on” position to get more musical results from the ring modulator.
32 Effects
Dave Smith Instruments
HAL:
This is a Hall reverb. It’s the largest of the available reverbs. Adjustable parameters are reverb time and early reflection amount.
rOO:
This is a Room reverb. It’s the second largest of the available reverbs.
Adjustable parameters are reverb time and early reflection amount.
PLA:
This is a Plate reverb. It emulates a classic reverb plate. Adjustable parameters are reverb time and early reflection amount.
SPr:
This is a Spring reverb. It emulates a vintage, guitar-amp-style reverb. Adjustable parameters are decay and tone.
The OB-6 provides an analog distortion effect. This can be used to add warmth, harmonic complexity, and an aggressive edge to sounds.
The character of the distortion is affected by the harmonic content of a program. Sounds with more high-end will sound different than sounds with fewer harmonics.
To add distortion:
1. Press and hold the effect
button.
2. Turn the mix
knob to set the distortion amount.
3. Release the effect
button.
Press and hold for 1 second
ON/OFF EFFECT TYPE
Display changes to “Dist”
Turn Mix knob to set amount
EFFECTS
MIX
A B
Adding the Distortion effect
OB-6 Operation Manual
Distortion 33
The LFO is a special-purpose oscillator that produces a frequency below the range of human hearing. The LFO is typically used for periodic modulation such as vibrato (periodic pitch modulation) and tremolo
(periodic amplitude modulation).
The LFO on the OB-6 produces a variety of waveshapes, including sine, sawtooth, reverse sawtooth, square, and random. Though most often used for low-frequency modulation, the OB-6 LFO can actually function at speeds that extend into the audible range for extreme effects.
FREQUENCY
LFO SYNC
LFO
SHAPE
SINE
SAWTOOTH
REV SAW
SQUARE
INITIAL AMT
RANDOM
VCO 1 VCO 2 PULSE WIDTH
AMP
1 2
FILTR FREQ FILTR MODE
The Low-Frequency Oscillator
Sine and Random waves are bipolar. That is, their waveshape is positive for half of their cycle and negative for the other half. In the case of the sine wave, this makes it possible to generate a natural-sounding vibrato that goes alternately sharp and flat in equal amounts on either side of a center frequency. Random, also known as “sample and hold,” generates a series of random values, each held for the duration of one cycle
The square wave, sawtooth, and reverse sawtooth generate only positive values. In the case of the square wave this makes it possible to generate naturalsounding trills.
34 Low Frequency Oscillator
Dave Smith Instruments
Triangle Sawtooth Reverse
Sawtooth
Square
0
LFO waveshapes
Random
The OB-6 has a sixth “hidden” LFO waveshape that you can use as a modulation source — noise. To access this, choose random
then turn frequency
all the way clockwise. This generates a white noise waveform.
The LFO can be free-running or synced to the arpeggiator, sequencer, or
MIDI clock for tempo-synced effects such as filter sweeps, tremolo, and so on.
Frequency:
Sets the frequency of the LFO waveshape routed to the destination from a slow .022Hz to a fast 500Hz. See also “LFO Sync” below.
LFO Sync:
When on, the LFO synchronizes with the arpeggiator, sequencer, or MIDI clock. By default, the LFO wave cycle is reset when you press a key (but is not reset if you press a key while other notes are held).
Shape:
Sine, Sawtooth, Reverse Sawtooth, Square, Random
—The wave shape of the LFO. A sixth waveshape, noise, can be generated by selecting random
and turning the frequency
knob all the way to the right.
Initial Amount:
Sets the amount of LFO modulation routed to the selected destinations. Setting an amount here applies the selected modulation continuously. If you set this parameter to zero but still select a modulation destination, modulation is only applied when you use the
Mod Wheel.
VCO 1:
Selects the frequency of Oscillator 1 as a modulation destination. Use a sine wave as a source to create vibrato. Use a square wave to create trills.
VCO 2:
Selects the frequency of Oscillator 2 as a modulation destination. Use a sine wave as a source to create vibrato. Use a square wave to create trills.
OB-6 Operation Manual
Low Frequency Oscillator 35
Pulse Width:
(
Individually selectable for Oscillator 1 and Oscillator 2)
When Oscillator 1 or 2 are set to square wave, this modulates the pulse width of the wave. Use a sine wave LFO to create a chorus-like effect often used to emulate strings.
Amp:
Selects the amplitude level as a modulation destination. Use a sine wave LFO to create a tremolo effect.
Filtr Freq:
Selects the filter cutoff frequency as a modulation destination.
Use a sine wave LFO to create an auto-wah effect when in low-pass filter mode. Modulating the filter at high frequencies can create interesting timbres.
Filtr Mode:
Selects the filter mode as a modulation destination, changing smoothly between low-pass, notch, and high-pass modes. Modulating the filter at high frequencies can create interesting timbres.
Although the overall sonic character of the OB-6 is determined by its analog oscillators and filters, much of its power to make truly unique and unusual sounds comes from the X-Mod section.
X-MOD
FILTER ENV VCO 2
VCO 1 SHAPE 1
PW 1
FILTR FREQ FILTR MODE
The X-Mod section
36 X-Mod
Dave Smith Instruments
X-Mod modulation sources:
• Filter envelope
• VCO 2 frequency
X-Mod modulation destinations:
• VCO 1 frequency
• VCO 1 waveshape
• VCO 1 pulse width
• Filter cutoff frequency
• Normal to Bandpass filter mode
• Filter mode (Low-Pass, Notch, High-Pass)
You can control how much the source affects the destination by dialing in a specific modulation amount with the filter env
or vco
2
knobs.
Modulation amount can either be positive or negative.
Use X-Mod to create complex harmonic effects ranging from FM
(frequency modulation) to audio-rate filter modulation and beyond. Many classic sounds on the original Oberheim OB-series of synthesizers were created through clever use of X-Mod.
X-Mod Parameters
Filter Env:
Selects the amount of modulation from the Filter Envelope that is applied to a selected destination. Modulation amount can be either positive or negative.
VCO 2:
Selects the amount of modulation from Oscillator 2 that is applied to a selected destination. Modulation amount can be either positive or negative.
When using vco
2
as a modulation source, the modulation character is affected by the waveshape currently chosen for Oscillator 2 (triangle, sawtooth, or square/pulse). Try setting Oscillator 2 to low frequency (using the low freq
switch) to further increase modulation possibilities.
OB-6 Operation Manual
X-Mod 37
VCO 1:
Selects Oscillator 1 frequency as a modulation destination.
Choose vco
2
as a modulation source to produce FM effects with their characteristic complex harmonics and metallic timbre.
Shape 1:
Selects the Oscillator 1 waveshape as a modulation destination.
This can animate the timbre of Oscillator 1 in interesting ways.
PW 1:
When Oscillator 1 is set to pulse wave, choosing this as a destination modulates its pulse width. This will animate the timbre of Oscillator 1 in interesting ways.
Norm - BP:
Selects the filter mode as a modulation destination, changing smoothly between normal filter behavior (low-pass, notch, and high-pass modes) and bandpass mode.
Filtr Freq:
Selects the filter cutoff frequency as a modulation destination.
Use a sine wave LFO to create an auto-wah effect when in low-pass filter mode. Modulating the filter at high frequencies can create interesting timbres.
Filtr Mode:
Selects the filter mode as a modulation destination, changing smoothly between low-pass, notch, and high-pass modes. Modulating the filter at high frequencies can create interesting timbres.
The OB-6 has a full-featured Arpeggiator. Turn it on, hold a chord and the OB-6 will play a pattern based on the individual notes held. Choose a mode (up, down, random, etc.), an octave range (1, 2, or 3), and a tempo, then pair it with an appropriately percussive sound, and you’ll be surprised at the number of creative things you can do.
When hold
is active, the Arpeggiator is in “relatch” mode, where playing a new chord latches to the new chord rather than adding notes to the existing chord.
38 X-Mod
Dave Smith Instruments
If you enable hold
, you can release the notes on the keyboard and the
Arpeggiator will continue to play. In addition, the Arpeggiator features auto-latching: With hold
on, played notes are held on and arpeggiated, and any additional notes you play are added to the arpeggio—as long as at least one key is continuously held.
You can sync the Arpeggiator to external MIDI clock, or even an external audio signal. When the Arpeggiator is playing, the Sequencer is disabled.
TAP TEMPO BPM
CLOCK
VALUE ON/OFF
ARPEGGIATOR
OCTAVES MODE
1
2
3
SEQUENCER
RECORD PLAY
The Arpeggiator section
To use the Arpeggiator:
1. Press the Arpeggiator on
/ off switch to turn it on.
2. Hold down one or more notes on the keyboard. The Arpeggiator plays them according to the settings you’ve chosen.
3. To latch arpeggiation on (so that you don’t have to continuously hold down notes) press the hold
button.
4. Adjust settings such as mode
, octave
, repeats
, bpm and value
.
5. To synchronize a delay effect to the Arpeggiator, turn on clock sync
in the Effects section, choose a delay, and adjust its delay time setting as desired.
An audio signal connected to the rear-panel footswitch
- sequence
jack can be used to control arpeggiator (and sequencer) playback. This makes it possible to tempo sync the arpeggiator to a recorded drum track or other audio source. Audio signals used to drive the arpeggiator/sequencer should not exceed 5 volts peak-to-peak. See “Seq
Jack” on page 13 for more information about choosing the appropriate mode for these behaviors.
OB-6 Operation Manual
X-Mod 39
Arpeggiator Parameters
Tap Tempo
—
Tapping the tap tempo
button sets the tempo from 30 to
250 BPM. The LED flashes at the BPM rate you set. Tap the button at least 4 times to set the tempo.
BPM:
30…250—
Sets the tempo for the arpeggiator in BPM (beats per minute). The tap tempo
LED flashes at the BPM rate. When lfo sync
is enabled on the low-frequency oscillator, or clock sync
is enabled in the
Effects section, the BPM rate affects the LFO frequency and/or delay effect.
When syncing to an external MIDI clock source, the BPM setting has no effect.
Value
—
Selects a basic note value relative to the BPM. See the table below:
Name
Half
Qtr
8th
8th D
8th S
8th T
16th
16th S
16th T
32nd
Tempo
BPM/2
BPM
Timing Division
Half note
Quarter note
BPM x 2 Eighth note
BPM x 2 Eighth note, dot
BPM x 2 Eighth note, swing timing
BPM x 3 Eighth note triplets
BPM x 4 Sixteenth note
BPM x 4 Sixteenth note, full swing timing
BPM x 6 Sixteenth note triplets
BPM x 8 Thirty-second note
On/Off
—
Turns the Arpeggiator on and off.
Octave:
1 Octave, 2 Octaves, 3 Octaves—
Set to 1 Octave, only the keyed notes are arpeggiated. Set to 2 Octaves, the keyed notes and the notes one octave above them arpeggiate. Set to 3 Octaves, the keyed notes and the notes one and two octaves above them arpeggiate.
40 X-Mod
Dave Smith Instruments
Mode:
Sets the order in which notes play when Arpeggiator is on. See the table.
Arp Mode
Up
Down
Up + Down
Random
Assign
Behavior
Plays from lowest to highest note
Plays from highest to lowest note
Plays from lowest to highest and back to lowest
Plays notes in random order
Plays notes in the order the keys were pressed
The OB-6’s sequencer is similar to a classic step sequencer. It allows you to create a single sequence of up to 64 steps, including rests and ties, with up to 6 notes per step. In addition, you can play along with a sequence
(provided there is available polyphony), making it a powerful live performance tool. When the Sequencer is playing, the Arpeggiator is disabled.
CLOCK
TAP TEMPO
BPM
The Sequencer/Arpeggiator
VALUE
ARPEGGIATOR
ON/OFF
OCTAVES MODE
SEQUENCER
RECORD PLAY
An audio signal connected to the rear-panel footswitch
- sequence
jack can be used to control sequencer playback. This makes it possible to tempo sync the sequencer (or arpeggiator) to a recorded drum track or other audio source. Audio signals used to drive the arpeggiator/sequencer should not exceed 5 volts peak-topeak. See “Seq Jack” on page 13 for more information about choosing the appropriate mode for these behaviors.
Programming the Sequencer
Though programming the sequencer is simple, you can create sequences that are rhythmically and melodically complex by combining a repeating phrase or bass line with chords, ties, and rests. You can play up to 64 steps with up to 6 notes held simultaneously per step. For most sequences you’ll probably want to use sounds with a relatively sharp attack and short release.
OB-6 Operation Manual
Sequencer 41
Most factory programs have a sequence associated with them. Recall a program and press the Sequencer’s play button to hear its associated sequence.
To program a note sequence:
1. Press the record
button.
2. Perform the sequence on the keyboard. The display indicates the current step as you play.
When recording a chord as a step, as long as you continue to hold at least one note down, you can keep adding notes to the chord/step, and even use the transpose buttons to extend the keyboard range while doing it.
3. To add a rest as you play, press the tens
/ increment
button for that step, then continue playing.
4. To add a “tie” that extends the length of a note, continue to hold down the note(s) and press the tens
/ increment
button repeatedly to extend the note the number of steps you want.
5. To step back a step in the sequence, press the bank select
/ decrement button. This will step back to the previous step so that you can rerecord it. (Stepping back erases the step.)
6. When you’re done, press play
to listen to your sequence.
7. To save the sequence, save the program and they are saved together.
(See “Saving a Program” on page 5.)
If you want to play live along with the sequencer, be sure to leave voices available. In other words, don’t play 6-note chords for every step in the sequence!
To play a sequence:
1. Press play
. The sequence plays back at the current BPM setting.
2. To stop playback, press play again .
Alternatively, you can start and stop sequencer playback using a footswitch connected to the rear-panel seq
jack or using MIDI start/stop messages sent from a
DAW or other MIDI device. See “Seq Jack” on page 13 for more information.
42 Sequencer
Dave Smith Instruments
Use the bpm
, value
, or tap tempo
controls to adjust sequencer playback speed.
To transpose a sequence:
1. Press play
. The sequence begins playback.
2. Press and hold record and press a key on the keyboard. “Middle C” is the reference point. Playing a note above middle C transposes the sequence higher by that interval. Playing a note below middle C transposes the sequence lower by that interval.
Sequencer Parameters
Here are the controls and parameters used when interacting with the sequencer.
Record:
On, Off—
This switch turns sequencer recording on and off.
Play:
On, Off—
This switch turns sequencer playback on and off.
BPM:
30…250—
Sets the tempo for the Sequencer and Arpeggiator in BPM
(beats per minute). The tap tempo
LED flashes at the BPM rate. When lfo sync
is turned on, the BPM rate affects the LFO frequency. When syncing to an external MIDI clock source, the BPM setting has no effect.
Tap Tempo:
30…250—
Tap this button at least 4 times to quickly set the tempo for the Sequencer and Arpeggiator. The LED flashes at the BPM rate you set.
OB-6 Operation Manual
Sequencer 43
Value:
Sets the note value for each sequencer/arpeggiator step relative to the BPM. value
works with both internal and external clock sources.
The following table lists the values:
Name
Half
Qtr
8th
8th D
8th S
8th T
16th
16th S
16th T
32nd
Tempo
BPM/2
BPM
BPM x 2
BPM x 2
BPM x 2
BPM x 3
BPM x 4
BPM x 4
BPM x 6
BPM x 8
Timing Division
Half note
Quarter note
Eighth note
Eighth note, dot
Eighth note, swing timing
Eighth note triplets
Sixteenth note
Sixteenth note, full swing timing
Sixteenth note triplets
Thirty-second note
44 Sequencer
Dave Smith Instruments
The master output level of the OB-6 is controlled by the front-panel master volume
knob in the output
section. In addition, the volume of an individual program can be set with the prgm vol
knob in same section.
This is useful for ensuring that your sounds have roughly the same volume from program to program. Unison sounds in particular can be very loud compared to other programs.
PAN SPREAD PRGM VOL
MASTER VOLUME
The Output section
To set the volume of an individual program:
1. Choose a program.
2. In the output
section, turn the prgm vol
knob to set its volume.
3. Save the program. (See “Saving a Program” on page 4.)
MIDI volume can also influence the overall volume of the OB-6 if you are controlling it from an external MIDI source.
OB-6 Operation Manual
Sequencer 45
Pan Spread pans audio in the stereo field individually per voice. Set to
0, all voices are panned to the center. As you turn the pan spread
knob up, the audio in each voice is gradually moved away from the center by greater amounts. Every other voice goes in a different direction, left or right. This creates a broader stereo field while playing..
The up
and down
buttons in the transpose
section transpose the keyboard up or down in octaves. The LED indicates the current keyboard transposition state. Transposing the keyboard also changes the MIDI note numbers of the keys so that MIDI notes sent are also transposed. Transpose settings are global and are not saved with individual programs.
TRANSPOSE
0
The Transpose controls
When hold
is on, any notes played will continue to play until hold
is turned off. When used in conjunction with the Arpeggiator, notes are latched on and replaced by any new note(s) struck. If hold
is on and at least one key continuously held down, any new notes played are added to the arpeggio.
HOLD
The Hold button
46 Sequencer
Dave Smith Instruments
Portamento causes the pitch of a note to glide up or down from the pitch of the previously played note. Portamento is turned on and off using the portamento
switch, but the rate
must also be set. If the portamento button is on, but rate amount
is set to 0, portamento
has no effect.
RATE PORTAMENTO
The Portamento controls
There are four modes that determine how portamento behaves.
Fixed Rate (
FR
):
The time to transition between notes varies with the interval between the notes; the greater the interval, the longer the transition time. The portamento rate is fixed. This is the default portamento mode.
Fixed Rate A (
FRA
):
The same as Fixed Rate, but portamento is only applied when playing legato. That is, portamento only occurs when a note is held until the next note is played. This effectively allows portamento to be turned on and off from the keyboard.
Fixed Time (
FT
):
Portamento is set to a fixed time, regardless of the interval between notes.
Fixed Time A (
FTA
):
The same as Fixed Time, but portamento only occurs when playing legato.
To select a portamento mode:
1. Press and hold the portamento
switch. The numeric display shows the currently selected portamento
mode.
2. To select a different mode, continue to hold down the portamento switch then press the bank
/ decrement
and tens
/ increment switches to step through the other choices.
3. When finished, release the portamento
switch.
OB-6 Operation Manual
Portamento 47
When unison
is on, the OB-6 functions like a monophonic synthesizer in that only 1 note can be played at a time. However, that one note can be powered by as many as six voices, depending on how many you choose to use. With up to 12 oscillators powering a single note (2 oscillators per voice x 6 voices), you can create some very dense, speaker-rattling sounds.
If you want to create an ultra heavy synth bass, try using Unison!
Unison gives you control over not only how many voices to stack, but also the amount of detuning (with the detune
knob) between the oscillators, and what note gets priority if you happen to play more than one note on the keyboard. (This is called the key assign mode or
note priority
. See “Key Assign Modes” on page 50 for details.)
When Unison is enabled, the detune knob not only detunes the unison voices but also spreads them out in the stereo field. If an odd number of voices are stacked, one voice is placed in the center of the stereo field with the other voices spread right and left. The higher the detune
setting, the wider the stereo spread.
DETUNE UNISON
The Unison button
48 Unison
Dave Smith Instruments
To use Unison:
1. Press and hold the unison
switch.
2. With the Unison switch held down, use the bank
/ decrement
and tens
/ increment switches to choose the number of voices to stack, then release the Unison switch.
3. To detune the oscillators, use the detune
knob.
Using Chord Memory
Unison has another useful feature: chord memory. Instead of assigning voices to a single note, hold down a chord on the keyboard and press the
Unison switch. The OB-6 memorizes the notes of the chord. Single notes played on the keyboard will then trigger all notes of the stored chord, transposing them as you play up or down the keyboard. Try using this feature to create powerful chord stabs and hits.
If you save a program that uses chord memory, the chord is saved with the program. “
CHD
” will then appear as a choice if you step through voice stacking options using the banks
/ decrement
and tens
/ increment buttons while holding down unison
.
If low-note priority is chosen in Global settings, the note that you play corresponds to the lowest note of the chord voicing. Changing the Key Assign Mode to high-note priority will make the note that you play correspond to the highest note in the chord voicing.
To use chord memory:
1. Hold down a chord on the keyboard (6 notes maximum).
2. Press the unison
switch. The chord voicing is memorized. Play a few notes to listen to the result.
3. If you save the program, the unison chord memory is saved with it.
To clear chord memory:
1. Turn off Unison.
2. Hold down a single note.
3. Press the unison
button.
4. Save the program again.
OB-6 Operation Manual
Unison 49
Key Assign Modes
Key Assign (sometimes called note priority) determines what note has priority when more than one note is played on the keyboard or via MIDI:
• Low-Note Priority (
LO
) is most common in vintage synths and is often used for playing trills by holding a note and repeatedly tapping a lower note.
• Low Retrigger (
LOr
) causes the envelopes to be retriggered with each keystroke.
• High Note (
Hi
) and High Retrigger (
Hir
) are similar to the low note settings, except that the highest note is given priority.
• Last Note (
LAS
) and Last Retrigger (
LAr
) give priority to the last note played.
To choose the Key Assign mode:
1. Press and hold key mode
. The numeric display shows the currently selected mode.
2. To select a different mode, continue to hold down the key mode
switch then press the bank
/ decrement
and tens
/ increment switches to step through the other choices.
3. Release the key mode
switch when you’re finished.
Key Assign settings are only relevant to Unison mode. They do not affect polyphonic playback.
KEY MODE DETUNE UNISON
The key mode
button
50 Unison
Dave Smith Instruments
The write
button saves the currently active program. Saving a program overwrites a previously saved program.
The OB-6 contains a total of 1000 programs. 500 are permanent and
500 can be overwritten. Banks 0-4 are User Banks that can be overwritten. Banks 5-9 are Factory Banks that are permanent. You can edit the programs of either bank, but you can only save them to Banks 0-4. As shipped from the factory, presets 000-499 are identical to 500-999.
WRITE
The Write button
Decrement
BANK BANK PROGRAM
Increment
TENS
Transpose
Local Ctrl
Master Tune MIDI Channel
Seq Jack Pot Mode
MIDI Clock
Sustain +/-
Clock Port
Alt Tuning
Param Xmit Param Rcv MIDI Control MIDI SysEx
Vel Response AT Response Stereo/Mono Pgm Dump
MIDI Out
SELECT SELECT 0 1
Program bank, tens, and number selectors
2 3 4 5 6 7 8 9
To save a program to the same preset location:
1. Press the write
button. Its LED begins blinking.
2. Press a program selector
button (0-9) to specify the “ones” digit of the program.
3. The write
button LED stops blinking and the program is saved.
To save a program to a different bank location:
1. Press the write
button. Its LED begins blinking.
2. Hold down the bank button then press a program selector
button (0-9) to specify the “hundreds” bank of the program. You can only save to
Banks 0-4.
3. Hold down the tens button then press a program selector
button (0-9) to specify the “tens” digit of the program.
4. Press a program selector
button (0-9) to specify the “ones” digit of the program.
5. The write
button LED stops blinking and the program is saved.
OB-6 Operation Manual
Write 51
Canceling Save
Sometimes you may want to cancel saving a program before you commit.
To cancel the Save process before you commit:
• If the write
button LED is flashing, press it again. The LED stops flashing and saving is canceled. You can return to editing if you want.
Comparing Before You Save
Before writing a program to a new location, it’s a good idea to listen to the program in the target location to make sure you really want to overwrite it.
To evaluate a program before you overwrite it:
1. Get ready to save by pressing the write
button. It starts flashing.
2. Press the global
button. Both LEDs on the button light up, indicating compare
mode.
3. Use the program buttons to navigate to the sound you want to compare and play the keyboard to hear the sound.
4. To disable the compare function and go back to the edited sound, turn off the global
button. Programs can’t be written while in compare mode.
5. If you want to save the edited sound, the write
button is still flashing and ready to save, so enter a location with the program buttons. The sound is saved.
6. Alternatively, if you want to cancel saving and continue editing, press the write
button. It stops flashing and saving is canceled.
52 Write
Dave Smith Instruments
Global settings are parameters that affect all programs. These include settings such as Master Tune, MIDI Channel, MIDI Clock, and others.
Global parameters are printed in two rows the program number switches
(0 - 9). Press the globals
button once to access the top row. Press it twice to access the bottom row. For details on the various Global parameters, see “Global Settings” on page 10.
GLOBALS
The Globals button
To change a Global setting:
1. Press the globals
button. Pressing it once accesses the top row of
Global parameters. Pressing it twice accesses the top row of Global parameters. The LED indicates which row is active.
2. Press the program selector
button that corresponds to the Global parameter you want to change.
3. Use the bank
/ decrement
and tens
/ increment
buttons to step through the available settings until you reach the one you want.
4. When finished, press globals
again to exit.
Pressing the globals
button three times in a row saves the current program as the default program that appears when you turn on the OB-6.
OB-6 Operation Manual
Globals 53
The manual
switch toggles “live panel” mode on and off. In live panel mode the OB-6 ignores the currently active preset and reverts to the current front-panel settings of its knobs and switches. In other words, what you see on the front panel is what you hear. This is a great mode for learning, experimentation, and instant gratification.
MANUAL
The Manual button
To enter live panel mode:
• Press the manual
button to toggle it on. The OB-6 is now in live panel mode. What you see on the front panel is what you hear. Note that you can’t change programs or banks with manual
on.
To return to preset mode:
• Press the manual
button again to toggle it off. The LED is off. The current program is what you hear.
Be aware when entering live panel mode that the current settings of the OB-6 knobs and switches may be such that no sound is produced. This could because the
Mixer levels are all set to zero, or some other reason. See
Appendix B: Troubleshooting and Support
for a checklist that can help you identify the cause.
54 Manual
Dave Smith Instruments
The OB-6 has a spring-loaded Pitch wheel and a Mod wheel. You can use these controls to enhance live performance by bending notes and adding modulation in real time as you play.
In the same way that guitar players use note bends and vibrato to give their playing expressiveness and character, these two controls can really help you define your sound as a performer and take you beyond just playing notes on the keyboard.
Pitch Mod
The Pitch and Modulation wheels
Pitch Wheel
You can set a range in semitones for the Pitch wheel, depending on your playing preference. The range is up to 12 semitones (1 octave). Many musicians use a range of 2 semitones (a whole step) since this is the bend range of many acoustic instruments. For guitar whammy bar effects, you many wish to set a wider range.
To set the pitch bend range:
1. Press and hold the whl range
button.
2. With the button still held down, use the bank
/ decrement
and tens
/ increment switches to choose the number of semitones (up to 12) for the pitch bend range, then release the whl range
button.
OB-6 Operation Manual
Pitch and Mod Wheels 55
Modulation Wheel
The Mod wheel controls the amount of modulation applied to any destinations chosen in the low
frequency oscillator
section. This allows you to
“perform” LFO modulation in real time by moving the Mod wheel. This is a great way to add expressiveness to a sound or performance.
To choose a modulation destination for the Mod wheel:
1. In the low
frequency oscillator
section, choose a modulation destination as well as a shape
and frequency
for the LFO. (See “Low
Frequency Oscillators” on page 34 for more details.)
2. To apply modulation only when using the Mod wheel, set the initial amt
knob to zero. (Turning this knob up will apply LFO modulation continuously — not just when the Mod wheel is used.)
Many programs use the Mod wheel to add vibrato. In this case, vco 1 and vco 2 are enabled as modulation destinations in the low
frequency oscillator
section. This adds vibrato when you push the mod wheel forward. Set the initial amt
knob to zero to apply vibrato only when using the Mod wheel.
Aftertouch is a performance feature that allows you to add modulation to a sound by applying additional pressure to a key after the key is already down. The greater the pressure applied, the more modulation is applied.
The OB-6 provides
monophonic
(or “channel”) aftertouch, which means that applying pressure to any key within a chord will apply modulation to
all
notes currently held.
The Aftertouch section lets you choose the amount of modulation applied using aftertouch and which parameters are modulated (oscillator frequency, filter frequency, etc.). You can set either a positive or negative amount.
For example, if you select the filter cutoff frequency as destination ( filt freq
), set a
positive
amount of aftertouch, then press the keys harder, the filter cutoff frequency will increase, making the filter open wider and the sound become brighter.
56 Aftertouch
Dave Smith Instruments
Conversely, if you select the filter frequency as destination, set a
negative
amount of aftertouch, then press the keys harder, the filter cutoff frequency will be lowered, making the filter close more and the sound become more muted.
The OB-6 provides four different aftertouch response settings for your convenience. The default setting provides a linear response. To choose a different response curve, use the at response
button in the globals
section. See page 14 for more details.
AFTERTOUCH
AMOUNT
VCO 1 VCO 2
LFO AMT LOUDNESS
FILTR FREQ FILTR MODE
The Aftertouch controls
Amount:
Selects the amount of aftertouch applied to a selected destination. Positive amount
settings apply positive amounts of modulation.
Negative amount
settings apply negative amounts of modulation.
VCO 1:
Selects Oscillator 1 frequency as an aftertouch modulation destination. With a positive amount
setting, pressing the keys harder will shift the Oscillator 1 pitch upward. With a negative amount
setting, pressing the keys harder will shift the Oscillator 1 pitch downward.
OB-6 Operation Manual
Aftertouch 57
VCO 2:
Selects Oscillator 2 frequency as an aftertouch modulation destination. With a positive amount
setting, pressing the keys harder will shift the Oscillator 2 pitch upward. With a negative amount
setting, pressing the keys harder will shift the Oscillator 2 pitch downward.
LFO Amount:
Selects the lfo amount
parameter as an aftertouch modulation destination. With a positive amount
setting, pressing the keys harder will increase the amount of LFO modulation to any destination selected in the low
frequency oscillator
section. With a negative amount
setting, pressing the keys harder will increase the amount of
LFO modulation — with the LFO waveform inverted.
Loudness:
Selects Amplitude as an aftertouch modulation destination.
With a positive amount
setting, pressing the keys harder will increase the volume of a sound. With a negative amount
setting, pressing the keys harder will decrease the volume of a sound.
If the Loudness Envelope’s amount
is set to full, positive amounts of loudness aftertouch will have no effect since the VCA is already at its maximum output level.
Filtr Freq:
Selects the filter cutoff frequency as a modulation destination.
With a positive amount
setting, pressing the keys harder will open the filter wider and make a sound become brighter. With a negative amount setting, pressing the keys harder will close the filter more and make a sound more muted.
Filtr Mode:
Selects the Filter Mode as a modulation destination. With a positive amount
setting, pressing the keys harder will move smoothly between low-pass, notch, and high-pass filter modes.
58 Aftertouch
Dave Smith Instruments
You can use the pgm dump
command in the globals
section
to transmit the current program, bank, or all banks in SysEx format via the selected
MIDI port. This allows you to save your programs so that you can share them or archive them.
To export a program or bank as a SysEx file over MIDI:
1. Press the globals button once (this enables the upper set of parameters) then press program selector 8 to select the midi sysex
command.
2. Use the bank
/ decrement
and tens
/ increment
buttons to select the appropriate MIDI port — MIDI (
MID
) or USB ( usb
) .
3. Press globals a second time (this enables the lower set of parameters) then press program selector 8 to select the pgm dump
command. The write
button begins flashing.
4. Use the bank
/ decrement
and tens
/ increment
buttons to select the desired option — program (
PRO
) , tens ( ten
) , bank ( ban
) , user banks
(
USR
), all ( all
) .
5. Press write
. The program or bank is exported.
Dumped programs will load back into the same bank and program location in memory when received by the OB-6 via MIDI.
OB-6 Operation Manual
Exporting Programs and Banks 59
The OB-6 is calibrated at the factory. Controls such as the pitch and mod wheels shouldn’t require re-calibration. However, because its oscillators and filters are voltage controlled and can be affected by extremes of temperature, you may need to use the built-in calibration function to tune them occasionally.
How and When to Calibrate the Oscillators and Filters
The first time you use the OB-6, please run its built-in oscillator and filter calibration procedure. Let it warm up for several minutes and come to its normal operating temperature before doing so.
Repeat the calibration procedure as needed over the next few days of use. The OB-6 learns the range of temperatures at your location and will keep itself in tune over this range.
Later, if you use the OB-6 in a different environment that is measurably warmer or cooler (on stage, in an air-conditioned studio, and so on) run the calibration procedure again.
To calibrate the oscillators and filters:
1. Hold down the manual
button and press 0.
2. The front panel LEDs and display begin flashing as the OB-6 performs its auto-calibration procedure. Don’t turn off the power while it’s doing this.
3. When finished, the front panel controls will return to normal and you can play the OB-6 again.
60 Calibrating the OB-6
Dave Smith Instruments
Calibrating the Pitch and Mod Wheels
In general, the Pitch and Mod wheels shouldn’t require re-calibration.
However, if you experience what seems like a persistent problem with either of them, the OB-6 has built-in auto-calibration procedure that you can use to remedy the problem.
To calibrate the Pitch and Mod wheel’s low position:
1. Rotate and hold both wheels in their low position.
2. Hold down the manual
button and press 7.
To calibrate the Pitch wheel’s center position:
• With the Pitch wheel centered, hold down the manual
button and press 8.
To calibrate the Pitch and Mod wheel’s high position:
1. Rotate and hold both wheels in their high position.
2. Hold down the manual
button and press 9.
Resetting the Global Parameters
If you’re trying to track down a problem, it’s sometimes a good idea to reset the Global parameters to their defaults. This is a quick way to make sure that the OB-6 returns to its factory settings.
To reset all Global parameters to their default settings:
• Hold down the global
button and press write
.
OB-6 Operation Manual
Calibrating the OB-6 61
The OB-6’s USB 2.0 port enables bidirectional MIDI communication with a computer. A MIDI interface and MIDI cables are not necessary, just a USB cable. The OB-6 is a Class Compliant USB device.
That means it does not require any additional drivers to be installed to communicate with a Mac or Windows computer. The OB-6 transmits and receives MIDI data via USB, but does not transmit audio.
MIDI In and USB should not be used at the same time, as overlapping messages from different sources may cause the OB-6 to respond unpredictably. MIDI
Out and USB can be used at the same time and transmit the same data.
USB Notes
Under Mac OS X, “OB-6 Keyboard” will appear as a MIDI port when connected via USB and can be configured using the Mac’s Audio MIDI
Setup utility (typically found in Applications/Utilities).
Under Windows, the first time the OB-6 is connected via USB, the
“Found new hardware” alert appears and it is automatically installed as
“OB-6 Keyboard.”
In Windows, if you unplug the USB cable and plug it back in while a program has the OB-6 port open, you may have to resync. That usually means going to the OB-6 Keyboard Properties — in the Windows
Device Manager under “Sound, video, and game controllers” — and clicking OK. If
OB-6 Keyboard
is no longer listed in the Device
Manager, power the OB-6 down and back up again while it is connected via USB. It should be detected on power up.
62 Using USB
Dave Smith Instruments
By default, the OB-6 is set to standard, chromatic western tuning. Additionally it supports up to 16 additional alternative tunings, which you can access using the alt tuning
button in the globals
section.
From the factory, the OB-6 ships with 16 preset alternative tunings ranging from Equal temperament to Indonesian Gamelan tunings. If you want, you can replace these with other tunings that you can find on the
Internet. These must be in SysEx format. You can download them into the OB-6 using SysEx Librarian for Mac or MIDI-OX for Windows.
Here are descriptions of the default alternative tunings:
Nor
(Normal) 12 Tone Equal Temperament (non-erasable)
The default Western tuning, based on the twelfth root of two.
1. Harmonic Series
MIDI notes 36-95 reflect harmonics 2 through 60 based on the fundamental of A = 27.5 Hz. The low C on a standard 5 octave keyboard acts as the root note (55Hz), and the harmonics play upwards from there. The remaining keys above and below the 5 octave range are filled with the same intervals as Carlos’ Harmonic 12 Tone that follows.
2. Carlos Harmonic Twelve Tone
Wendy Carlos’ twelve note scale based on octave-repeating harmonics.
A = 1/1 (440 Hz). 1/1 17/16 9/8 19/16 5/4 21/16 11/8 3/2 13/8 27/16 7/4
15/8
3. Meantone Temperament
An early tempered tuning, with better thirds than 12ET. Sounds best in the key of C. Use this to add an authentic touch to performances of early
Baroque music. C=1/1 (260 Hz)
4. 1/4 Tone Equal Temperament
24 notes per octave, equally spaced 24root2 intervals. Mexican composer
Julian Carillo used this for custom-built pianos in the early 20th century.
OB-6 Operation Manual
Appendix A: Alternative Tunings 63
5. 19 Tone Equal Temperament
19 notes per octave (19root2) offering better thirds than 12 ET, a better overall compromise if you can figure out the keyboard patterns.
6. 31 Tone Equal Temperament
Many people consider 31root2 to offer the best compromise towards just intonation in an equal temperament, but it can get very tricky to keep track of the intervals.
7. Pythagorean C
One of the earliest tuning systems known from history, the Pythagorean scale is constructed from an upward series of pure fifths (3/2) transposed down into a single octave. The tuning works well for monophonic melodies against fifth drones, but has a very narrow palate of good chords to choose from. C=1/1 (261.625 Hz)
1/1 256/243 9/8 32/27 81/64 4/3 729/512 3/2 128/81 27/16 16/9 243/128
8. Just Intonation in A with 7-limit Tritone at D#
A rather vanilla 5-limit small interval JI, except for a single 7/5 tritone at D#, which offers some nice possibilities for rotating around bluesy sevenths. A=1/1 (440 Hz) 1/1 16/15 9/8 6/5 5/4 7/5 3/2 8/5 5/3 9/5 15/8
9. 3-5 Lattice in A
A pure 3 and 5-limit tuning which resolves to very symmetrical derived relationships between notes. A=1/1 (440 Hz)
1/1 16/15 10/9 6/5 5/4 4/3 64/45 3/2 8/5 5/3 16/9 15/8
10. 3-7 Lattice in A
A pure 3 and 7-limit tuning which resolves to very symmetrical derived relationships between notes. Some of the intervals are very close together, offering several choices for the same nominal chords. A=1/1
(440 Hz)
1/1 9/8 8/7 7/6 9/7 21/16 4/3 3/2 32/21 12/7 7/4 63/32
64 Appendix A: Alternative Tunings
Dave Smith Instruments
11. Other Music 7-Limit Black Keys in C
Created by the group Other Music for their homemade gamelan, this offers a wide range of interesting chords and modes. C=1/1 (261.625 Hz)
1/1 15/14 9/8 7/6 5/4 4/3 7/5 3/2 14/9 5/3 7/4 15/8
12. Dan Schmidt Pelog/Slendro
Created for the Berkeley Gamelan group, this tuning fits an Indonesianstyle heptatonic Pelog on the white keys and pentatonic Slendro on the black keys, with B and Bb acting as 1/1 for their respective modes. Note that some of the notes will have the same frequency. By tuning the 1/1 to
60 Hz, Dan found a creative way to incorporate the inevitable line hum into his scale. Bb, B = 1/1 (60 Hz)
1/1 1/1 9/8 7/6 5/4 4/3 11/8 3/2 3/2 7/4 7/4 15/8
13. Yamaha Just Major C
When Yamaha decided to put preset microtunings into their FM synth product line, they selected this and the following tuning as representative just intonations. As such, they became the de-facto introduction to JI for many people. Just Major gives preferential treatment to major thirds on the sharps, and a good fourth relative to the second. C= 1/1 (261.625)
1/1 16/15 9/8 6/5 5/4 4/3 45/32 3/2 8/5 5/3 16/9 15/8
14. Yamaha Just Minor C
Similar to Yamaha’s preset Just Major, the Just Minor gives preferential treatment to minor thirds on the sharps, and has a good fifth relative to the second. C= 1/1 (261.625) 1/1 25/24 10/9 6/5 5/4 4/3 45/32 3/2 8/5
5/3 16/9 15/8
OB-6 Operation Manual
Appendix A: Alternative Tunings 65
15. Harry Partch 11-limit 43 Note Just Intonation
One of the pioneers of modern microtonal composition, Partch built a unique orchestra with this tuning during the first half of the 20th century, to perform his own compositions. The large number of intervals in this very dense scale offers a full vocabulary of expressive chords and complex key changes. The narrow spacing also allows fixedpitched instruments like marimbas and organs to perform glissando-like passages. G = 1/1 (392 Hz, MIDI note 67)
1/1 81/80 33/32 21/20 16/15 12/11 11/10 10/9 9/8 8/7 7/6 32/27 6/5 11/9
5/4 14/11 9/7 21/16 4/3 27/20 11/8 7/5 10/7 16/11 40/27 3/2 32/21 14/9
11/7 8/5 18/11 5/3 27/16 12/7 7/4 16/9 9/5 20/11 11/6 15/8 40/21 64/33
160/81
16. Arabic 12-Tone
A 12-tone approximation of an Arabic scale, which appears in some electronic keyboards designed for use with Arabic music. Not a JI scale, nor equal tempered. These are the intervals in Cents relative to C:
60 = Cents 0.
61 = Cents +151.
62 = Cents +204.
63 = Cents +294.
64 = Cents +355.
65 = Cents +498.
66 = Cents +649.
67 = Cents +702.
68 = Cents +853.
69 = Cents +906.
70 = Cents +996.
71 = Cents +1057.
72 = Cents +1200
66 Appendix A: Alternative Tunings
Dave Smith Instruments
Troubleshooting
If you’re experiencing problems or unexpected behavior from your
OB-6, here are a few typical scenarios and their solutions:
If the OB-6 isn’t producing sound in live panel mode:
1. Enable live panel mode by pressing the manual
button.
2. Initialize a basic program by holding the manual
button and pressing the write
button.
3. If the problem is still there, return the instrument to live panel mode again and check all parameters to make sure they are at non-zero values. These parameters include:
• VCO 1 & 2 pitch
• VCO 1 & 2 mixer levels
• Program volume
• Master volume
• Set the Loudness Envelope amount
to max. Use a fast envelope with Sustain at max.
• Set VCO 1 & 2 to sawtooth
• Set filter cutoff to max
• Check all other parameters by physically changing them.
If the sequencer or arpeggiator has stopped running:
• Check the MIDI Clock setting in the Globals to ensure the OB-6 is set to out
or, if set to in
or slave thru
, make sure the OB-6 is receiving
MIDI clock.
If some of the programs sound different than usual:
• Check the Mod Wheel position. The Mod Wheel can do more than just add vibrato. Also, check the Clock settings in the Global menu to ensure the OB-6 is set to out
or, if set to in
or slave thru
, make sure the OB-6 is receiving MIDI clock.
OB-6 Operation Manual
Appendix B: Troubleshooting and Support 67
If there is a ground hum in the audio output:
• USB can cause ground loops, so try to resolve any grounding issues between the computer and the OB-6. Or use MIDI, which is opto-isolated.
If the OB-6 is behaving erratically.
• This is almost always caused by a MIDI data loop. Make sure that any
MIDI Thru functionality is turned off on the MIDI interface/hardware or in the MIDI software application. Disconnect all the OB-6’s MIDI connections—MIDI and USB cables—and see if the problem persists.
You can also monitor the MIDI traffic with MIDI Monitor (Mac OS) or
MIDI-OX (Windows) to see if the OB-6 is being overrun with duplicate messages.
If the OB-6 doesn’t seem to respond to its controls:
• Make sure Local Control is on in the Global settings.
If MIDI System Exclusive data is not transmitted/received:
• Make sure that the MIDI SysEx setting in the Global settings is set to usb
or midi
depending on which you are using to transmit or receive
MIDI messages.
If the OB-6 plays out of tune:
• Check Transpose and Master Tune parameters in the Global settings. If they seem correct, you may need to retune the oscillators. See “Calibrating the Prophet-6” on page 56. If this doesn’t help, recalibrate the pitch and mod wheels. “Calibrating the Pitch and Mod Wheels” on page 57.
If the pitch or mod wheel doesn’t go go full range:
• Recalibrate the pitch and mod wheels. See “Calibrating the Pitch and
Mod Wheels” on page 57.
If the filter sounds strange or out of tune:
• You may need to retune the filters. See “Calibrating the Prophet-6” on page 56.
If the OS Fails to Load Correctly When You Update:
• The OB-6 is equipped with a MIDI bootloader, which will allow you to reload the OS in the event the you accidentally “brick” your synth
(permanently freeze it) while updating its OS.
68 Appendix B: Troubleshooting and Support
Dave Smith Instruments
To restore your OB-6 if it is frozen.
1. Power on the OB-6 while holding the Write switch to enter bootloader mode. You’ll see an animation in the Effects Parameter 1 display.
2. Use a MIDI cable (not USB) to transmit the new OS to your synth. You must use a standard MIDI cable for this. USB MIDI doesn’t work in bootloader mode.
3. As the OS loads, you will see the main display count backwards from
999. When it gets to 0, another countdown will begin between the main display and the FX Parameter 1 display. Do not power down until this countdown has finished. The OB-6 will restart itself when it is done.
Contacting Technical Support
If you are still having a problem with the OB-6, contact Technical
Support at [email protected] Please include your
OB-6’s serial number, the version of the operating system (displayed in the Global screen), and the purchase date.
If you have not already reset the Global parameters and run the calibration routines (see Troubleshooting), you should do it before contacting Technical Support.
It’s probably the first thing they’ll ask you to do.
OB-6 Operation Manual
Appendix B: Troubleshooting and Support 69
Warranty Repair
Dave Smith Instruments warrants that the OB-6 will be free from defects in materials and/or workmanship for 1 year from the date of purchase.
Please register your product online at www.davesmithinstruments.com
to establish the date of purchase. (This is not a requirement for warranty service, but it will help expedite the process.)
Please contact [email protected] to determine the best course of action for getting your OB-6 repaired. For your own protection, as well as ours, please do not return any product to Dave Smith
Instruments without a return authorization (RA) number. To issue an RA number, Technical Support needs:
• Your name
• Your return address
• Your email address
• A phone number where you can be reached
• Your OB-6’s serial number
• The date of purchase and where purchased
If you need to return your instrument for repair, you are responsible for getting it to DSI. We highly recommend insuring it and packing in the original packaging. Damage resulting from shipping a product with insufficient packaging is not covered by warranty.
70 Appendix B: Troubleshooting and Support
Dave Smith Instruments
The OB-6 receives MIDI data according to the settings you have chosen in the global settings. In addition, there is interaction between some of the Program parameters that determine the overall response of OB-6 to
MIDI data. Following are the Global parameters that affect response to
MIDI:
MIDI Channel:
All
,
1
…
16
—
Selects which MIDI channel to send and receive data, 1 to 16. All receives on all 16 channels.
MIDI Clock:
messages:
Sets the OB-6’s ability to send and receive MIDI clock
•
Off
: MIDI Clock is neither sent nor received
•
Out
: MIDI Clock is sent, but not received
•
In
: MIDI Clock is received, but not sent
• Slave Thru ( i-0
): MIDI Clock is received and passed to MIDI Out
• In, No Start/Stop ( n55
): Receives MIDI Clock but does not respond to
MIDI Start or Stop command.
When set to in
or slave thru
, if no MIDI clock is present at the selected input, the arpeggiator and sequencer will not function.
Clock Port:
MID
,
USB
—
Sets the port(s), MIDI or USB, by which MIDI clock signals are received.
Param Xmit:
Off
,
CC
,
NR
—
Changes to the values of front panel controls are transmitted via MIDI as Continuous Controllers (
CC
) or Non-registered
Parameter Number (
NR
). Transmission of parameters can also be turned off.
NRPNs are the preferred method of parameter transmission, since they cover the complete range of all parameters, while CCs are limited to a range of 128.
Param Rcv:
Off
,
CC
,
NR
—
Sets the method by which parameter changes are received via MIDI. As with transmission, NRPNs are the preferred method.
OB-6 Operation Manual
Appendix C: MIDI Implementation 71
MIDI Control:
Off
,
On
—
When On, the synth will respond to MIDI controllers, including Pitch Wheel, Mod Wheel, Pedal, Volume.
MIDI Sysex:
MID
,
USB
—
When set to MIDI (
MID
) it will receive and transmit them using the MIDI ports/cables When set to USB it will receive and transmit them using the USB port/cable. MIDI SysEx messages are used when sending and receiving a variety of data including, programs, alternative tunings, system updates, and more.
MIDI Out:
MID
,
USB
—
Sets the port by which MIDI data will be transmitted (MIDI or USB)..
MIDI Messages
System Real-Time Messages
Status
1111 1000
Description
MIDI Timing Clock
Received Channel Messages
Status
1000 nnnn
1001 nnnn
1010 nnnn
1011 nnnn
1100 nnnn
Second
0kkkkkkk
0kkkkkkk
0kkkkkkk
0vvvvvvv
0ppppppp
Third
0vvvvvvv
0vvvvvvv
0vvvvvvv
0vvvvvvv
1101 nnnn
1110 nnnn
0vvvvvvv
0vvvvvvv 0vvvvvvv
Description
Note Off. Velocity is ignored
Note On. Note off if vvvvvvv = 0
Polyphonic Key Pressure
Control Change; see “Received Controller Messages”
Program change, 0-99 for Programs 1-100 within current Bank
Channel Pressure
Pitch Bend LS Byte then MS Byte
Notes: 0kkkkkkk nnnn
0vvvvvvv
Note number 0 — 127
Channel number 0 to 15 (MIDI channel 1-16).
Ignored if MIDI channel set to ALL
Value
72 Appendix C: MIDI Implementation
Dave Smith Instruments
Received Controller Messages
Status
1011 nnnn
1011 nnnn
Second
1
4
Third
0vvvvvvv
0vvvvvvv
Description
Mod Wheel: directly assignable controller
Foot Controller: directly assignable controller
1011 nnnn 7 0vvvvvvv
1011 nnnn
1011 nnnn
1011 nnnn
1011 nnnn
1011 nnnn
74
32
64
123
121
0vvvvvvv
0vvvvvvv
0vvvvvvv
0vvvvvvv
0vvvvvvv
Volume: Combined with Master Volume and Voice
Volume
Brightness: Added to filter cutoff frequency
Bank Select: 0 - 4 select user banks 0 - 4; 5 - 9 select factory banks 0 - 4; others ignored
Damper pedal: Holds envelopes in Sustain if 0100 0000 or higher
All Notes Off: Clear all MIDI notes
Reset All Controllers: Clears all MIDI controllers to 0,
MIDI volume to maximum
See sections below for additional Continuous Controller (CC) and Nonregistered Parameter Number (NRPN) messages received.
Transmitted Channel Messages
Status
1000 nnnn
1001 nnnn
1011 nnnn
1100 nnnn
Second
0kkkkkkk
0kkkkkkk
0vvvvvvv
0ppppppp
Third
0000000
0vvvvvvv
0vvvvvvv
1101 nnnn
1110 nnnn
0vvvvvvv
0vvvvvvv 0vvvvvvv
Description
Note Off.
Note On.
Control Change; see “Transmitted Controller Messages”
Program change, 0-99 for Programs 00-99 within current Bank
Channel Pressure
Pitch Bend LS Byte then MS Byte
Notes: 0kkkkkkk nnnn
0vvvvvvv
Note number 0 — 127
Channel number 0 to 15 (MIDI channel 1-16).
Ignored if MIDI channel set to ALL
Value
OB-6 Operation Manual
Appendix C: MIDI Implementation 73
Transmitted Controller Messages
Status
1011 nnnn
1011 nnnn
1011 nnnn
1011 nnnn
1011 nnnn
1011 nnnn
1011 nnnn
Second
0000 0001
0000 0100
0000 0111
0100 1010
0010 0000
0100 0000
0000 0111
Third
0vvvvvvv
0vvvvvvv
0vvvvvvv
0vvvvvvv
0vvvvvvv
0vvvvvvv
0vvvvvvv
Description
Mod Wheel
Foot Controller: When assigned to Pedal 1 or Pedal 2
Volume: When assigned to Pedal 1 or Pedal 2
Brightness: When assigned to Pedal 1 or Pedal 2
Bank Select: 0 - 9
Damper pedal: Sends 0 if off, 0111 1111 when on
Volume knob
See sections that follow for additional Continuous Controller (CC) and
Non-registered Parameter Number (NRPN) messages transmitted.
74 Appendix C: MIDI Implementation
Dave Smith Instruments
Additional Continuous Controllers Transmitted/Received
The following table details how MIDI Continuous Controllers (CCs) are mapped to OB-6 controls. They are transmitted when Param Xmit is set to CC, and recognized/received when MIDI Rcv Receive is set to CC.
60
62
58
59
64
51
52
47
50
53
69
70
65
67
71
44
45
41
43
46
38
39
8
9
40
5
6
3
4
7
CC#
0
1
Param
VCA Env Release
Filter Env Amt
Filter Env Attack
Filter Env Decay
Filter Env Sustain
Filter Env Release
Arp On/Off
Arp Mode
Arp Octave
Arp Clock Division
Damper Pedal
Portamento On/Off
Osc 1 Freq
Osc 1 Level
Osc 1 Shape
Osc 1 Pulse Width
Bank Select MSB
Mod Wheel
BPM
Foot Controller
Portamento Time
Data Enttry MSB
MIDI Volume
Sub Octave Level
Distortion Amount
Data Entry LSB
Volume LSB
VCA Env Amt
VCA Env Vel Amt
VCA Env Attack
VCA Env Decay
VCA Env Sustain
104
105
106
107
120
99
100
101
102
103
96
97
78
79
98
CC#
74
75
76
77
125
126
127
121
122
123
124
Param
Brightness
Osc 2 Freq
Osc 2 Detune
Osc 2 Level
Osc 2 Shape
Osc 2 Pulse Width
Data Increment
Data Decrement
NRPN Param LSB
NRPN Param MSB
RPN Param LSB
RPN Param MSB
Filter Freq
Filter Resonance
Filter Key Amt
Filter Vel On/Off
Filter Mode
Band Pass On/Off
All Sound Off
Reset Controllers
Local Control On/Off
All Notes Off
Omni Mode Off
Omni Mode On
Mono Mode On
Poly Mode On
OB-6 Operation Manual
Appendix C: MIDI Implementation 75
NRPN Messages
The Non-Registered Parameter Number (NRPN) MIDI messages are used to transmit and receive both global and program parameters. They are transmitted when MIDI Parameter Send is set to NRPN in Global, and received when MIDI Parameter Receive is set to NRPN in Global.
The messages are handled in standard MIDI format using the NRPN CC commands in running status byte format. Below is the format used for transmitting a NRPN parameter.
Transmitted NRPN Messages
Status
1011 nnnn
0110 0011
0vvv vvvv
0110 0010
0vvv vvvv
0000 0110
0vvv vvvv
0010 0110
0vvv vvvv
Description
Control Change
NRPN parameter number MSB CC
Parameter Number MSB
NRPN parameter number LSB CC
Parameter Number LSB
NRPN parameter value MSB CC
Parameter value MSB
NRPN parameter value LSB CC
Parameter value LSB
The parameter number can be found in the two tables below, one for
Global parameters, and the other for Program parameters. The parameter numbers and the parameter values are broken into two 7-bit bytes for
MIDI transmission; the LSB has the seven least-significant bits, and the
MSB has the seven most-significant bits, though in most cases the MSB will be zero or one, and never more than two.
When receiving an NRPN, all messages do not necessarily need to be transmitted, since the synth will track the most recent NRPN number, though it is usually good practice to send the entire message above.
Once an NRPN is selected, the synth will also respond to NRPN Data
Increment and Decrement commands, which some controllers utilize.
Finally, it responds to one RPN (Registered Parameter Number) command, the RPN/NRPN Reset command, which can be handy for resetting the currently selected parameter to a known state.
76 Appendix C: MIDI Implementation
Dave Smith Instruments
Received NRPN Messages
Status
1011 nnnn
1011 nnnn
1011 nnnn
1011 nnnn
1011 nnnn
1011 nnnn
1011 nnnn
1011 nnnn
Second
0110 0011
0110 0010
0000 0110
0010 0110
0110 0000
0110 0001
0010 0101
0010 0100
Third
0vvvvvvv
0vvvvvvv
0vvvvvvv
0vvvvvvv
0xxxxxxx
0xxxxxxx
0111111
0111111
Description
NRPN parameter number MSB CC
NRPN parameter number LSB CC
NRPN parameter value MSB CC
NRPN parameter value LSB CC
NRPN parameter value Increment
NRPN parameter value Decrement
RPN parameter number MSB CC - Reset NRPN parameter number (when both MSB and LSB received)
RPN parameter number LSB CC - Reset NRPN parameter number (when both MSB and LSB received)
Global Parameter Data
The table shows the Global data sent and received on global parameter dumps, and corresponding NRPN number when sent/received individually.
NRPN
1024
1025
1026
1027
1028
1029
Range Description
0-100 Master Fine Tune
0-24
0-16
Master Coarse Tune
MIDI Channel
0 = All
0-3
0-1
0-2
MIDI Clock Mode
0 = Off
1 = Master
2 = Slave
3 = Slave Thru
MIDI Clock Port
0 = MIDI Port
1 = USB
MIDI Param Send*
0 = NRPN
1 = CC
2= Off
NRPN
1033
1035
1037
1039
1040
1030
1031
1032
0-2
0-1
0-1
MIDI Param Receive†
0 = NRPN
1 = CC
2= Off
MIDI Control Enable
0 = Off
1 = On
MIDI SysEx Enable
0 = Off
1 = On
1041
1042
1043
*Controller received, but not transmitted.
†Controller transmitted, but ignored when received.
1044
OB-6 Operation Manual
Range Description
0-3 MIDI Out Select
0 = Off
1 = MIDI
2 = USB
3 = MIDI+USB
0-1 Local Control*
0 = Off
1 = On
0-2
0-3
Pot Mode
0 = Relative
1= PassThru
2 = Jump
Seq Jack
0 = normal
1= trigger
2= gate
3= trigger+gate
0-3
Sustain Polarity
0 = normally open
1= normally closed
2= Sustain Normally Open/
Sequencer Normally Closed
3= Sustain Normally Closed/
Sequencer Normally Open
0-3 Velocity Response
0-3
0-1
0-16
Aftertouch Response
Mono/Stereo
0 = Stereo
1 = Mono
Alt Tuning
Appendix C: MIDI Implementation 77
0-164
0-255
0-2
0-1
0-1
0-1
0-1
0-127
0 -3
0-1
0-127
0-12
0-127
0-127
Value
0-60
0-1
0-127
0-255
0-255
0-60
0-254
0-127
0-254
0-255
0-1
0-127
0-127
0-127
0-127
0-127
0-127
64
66
62
63
67
68
28
29
11
27
9
10
7
8
5
6
3
4
1
0
2
47
48
45
46
49
50
32
33
30
31
NRPN
Program Parameter Data
The following table lists OB-6’s program parameters.
Description
Osc 1 Freq
Osc 1 Sync
Osc 1 Level
Osc 1 Shape
Osc 1 Pulse Width
Osc 2 Freq
Osc 2 Freq Fine
Osc 2 Level
Osc 2 Shape
Osc 2 Pulse Width
Osc 2 Low Freq
Osc 2 Key On/Off
Osc 1 Sub Level
Portamento Mode
Portamento On/Off
Portamento Rate
Pbend Range
Noise Level
Detune
Filter Freq
Filter Res
Filter Key Amt
Filter Vel On
Filter mode
Filter Normal -
Bandpass
Voice Volume
Pan Spread
Distortion Amt
VCA Env Amt
VCA Env Attack
VCA Env Decay
111
112
113
98
109
110
94
95
96
97
89
90
81
88
91
93
79
80
77
78
69
70
71
NRPN
114
115
0-1
0-1
0-1
0-1
0-1
0-1
0-1
0-1
0-1
0-127
0-254
0-255
0-4
0-1
0-1
Value
0-127
0-127
0-1
0-254
0-127
0-127
0-127
0-1
0-254
0-1
Description
VCA Env Sustain
VCA Env Release
VCA Env Vel On/Off
Filter Env Amt
Filter Env Attack
Filter Env Decay
Filter Env Sustain
Filter Env Release
LFO Freq
LFO Initial Amt
LFO Shape
LFO Sync
LFO Freq 1
Dest On/Off
LFO Freq 2
Dest On/Off
LFO PW 1, 2
Dest On/Off
LFO Amp Dest
On/Off,
LFO Filter Mode
Dest On/Off
LFO Amp Dest
On/Off
Pressure Amt
Pressure Freq 1
Dest On/Off
Pressure Freq 2
Dest On/Off
Pressure Low-pass
Dest On/Off
Pressure Filter
Mode Dest On/Off
Pressure VCA
Dest On/Off
Pressure LFO Amt
Dest On/Off
78 Appendix C: MIDI Implementation
Dave Smith Instruments
0-1
0-1
0-9
0-127
0-255
0-127
0-1
0-1
0-254
0-254
0-1
Value
0-5
0-127
0-255
0-127
0-1
0-1
0-1
0-1
0-1
0-4
0-2
0-9
0-1
0-6
0-5
30-250
32 - 125
12-108
0-127
12-108
Description
FX 1 Type
FX 1 Mix
FX 1 Param 1
FX 1 Param 2
FX 1 Sync
FX 2 Type
FX 2 Mix
FX 2 Param 1
FX 2 Param 2
FX 2 Sync
FX On/Off
XMod Filter Env Amt
XMod Osc 2 Amt
XMod Freq 1 Dest
On/Off
XMod Shape 1 Dest
On/Off
XMod PW
1 Dest On/Off
XMod Filter Dest
On/Off
XMod Filter Mode
Dest On/Off
XMod Norm-Bandpass Dest On/Off,
Unison On/Off
Unison Mode
Key Mode
Arp On/Off
Arp mode
Arp Range
Arp Tim Sig
BPM
Name 0-19
Seq Step 1-64
Note 1
Seq Step 1-64 Vel 1
Seq Step 1-64
Note 2
OB-6 Operation Manual
143
144
145
129
130
131
135
122
123
127
128
119
120
121
NRPN
146
147
148
149
150
160
161
162
163
156
157
158
167
236-255
256-319
320-383
384-447
NRPN
448-511
512-575
576-639
640-703
704-767
768-831
832-895
896-959
1035
1037
1039
1040
1030
1031
1032
1033
1041
1042
1043
1044
1089
960-1023
1024
1025
1026
1027
1028
1029
Appendix C: MIDI Implementation 79
0-1
0-2
0-3
0-3
0-2
0-1
0-1
0-3
0-3
0-3
0-1
0-16
0-127
0-127
0-100
0-24
0-16
0-4
0-1
0-2
Value
0-127
12-108
0-127
12-108
0-127
12-108
0-127
12-108
Description
Seq Step 1-64 Vel 2
Seq Step 1-64
Note 3
Seq Step 1-64 Vel 3
Seq Step 1-64
Note 4
Seq Step 1-64 Vel 4
Seq Step 1-64
Note 5
Seq Step 1-64 Vel 5
Seq Step 1-64
Note 6
Seq Step 1-64 Vel 6
Tuning Fine
Tuning Coarse
MIDI Channel
MIDI Clock
MIDI Clock Port
MIDI Param Send
MIDI Param Receive
MIDI MIDI Control
MIDI SysEx Control
MIDI Out
Local Control
Pot Mode
Seq Jack
Sustain Polarity
Velocity Response
At Response
Stereo Mono
Alt Tuning
Seq Transpose
Control NRPN Data
The following table lists the OB-6’s control NRPN data. It is received and transmitted but not saved as part of a program.
NRPN
1088
16256
Value
0-1
0-1
Description
Seq Play/Stop
Seq Rec On/Off
Status
1111 0000
0111 1110
0vvv vvvv
0000 0110
0000 0010
0000 0001
0010 1101
0000 0001
0000 0000
0000 0000
0jjj nnnn
1111 0111
Sysex Messages
Universal System Exclusive Message (Device Inquiry)
Status
1111 0000
0111 1110
0vvv vvvv
0000 0110
0000 0001
1111 0111
Description
System Exclusive (SysEx)
Non-realtime message
If MIDI channel is set to 1 - 16, 0vvvvvvv must match (unless MIDI Channel = ALL); always responds if 0vvvvvvv = 0111 1111.
Inquiry Message
Inquiry Request
End of Exclusive (EOX)
The OB-6 responds with:
Description
System Exclusive (SysEx)
Non-realtime message
If MIDI Channel = ALL, 0vvvvvvv = 0111 1111. Otherwise 0vvvvvvv = Channel Number
0 - 15.
Inquiry Message
Inquiry Reply
DSI ID
OB-6 ID (Family LS)
Family MS
Family Member LS
Family Member MS
Main Software version: jjj - Minor rev; nnnn - Major rev
End of Exclusive (EOX)
80 Appendix C: MIDI Implementation
Dave Smith Instruments
Request Program Dump
Status
1111 0000
0000 0001
0010 1110
0000 0101
0000 00vv
0vvv vvvv
1111 0111
Description
System Exclusive (SysEx)
DSI ID
OB-6 ID
Request Program Transmit
Bank Number, 0 - 9
Program Number, 0 - 99
End of Exclusive (EOX)
The OB-6 will respond by sending out the Program Data in the format described below in
Program Data Dump
.
Request Program Edit Buffer Dump
Status
1111 0000
0000 0001
0010 1110
0000 0110
1111 0111
Description
System Exclusive (SysEx)
DSI ID
OB-6 ID
Request Program Edit Buffer Transmit
End of Exclusive (EOX)
The OB-6 will respond by sending out the current Program edit buffer in the format described below in Program Edit Buffer Data Dump.
Request Global Parameter Dump
Status
1111 0000
0000 0001
0010 1110
0000 1110
1111 0111
Description
System Exclusive (SysEx)
DSI ID
OB-6 ID
Request Global Parameter Transmit
End of Exclusive (EOX)
The OB-6 will respond by sending out the current values of Global
Parameters in the format described in
Global Parameters Data Dump
.
OB-6 Operation Manual
Appendix C: MIDI Implementation 81
Program Data Dump
Status
1111 0000
0000 0001
0010 1110
0000 0010
0000 00vv
0vvv vvvv
0vvv vvvv
1111 0111
Description
System Exclusive (SysEx)
DSI ID
OB-6 ID
Program Data
Bank Number: 0 - 9
Program Number: 0 - 99
1024 bytes expanded to 1171 MIDI bytes in “packed MS bit” format
End of Exclusive (EOX)
Program Edit Buffer Data Dump
Status
1111 0000
0000 0001
0010 1110
0000 0011
0vvv vvvv
1111 0111
Description
System Exclusive (SysEx)
DSI ID
OB-6 ID
Edit Buffer Data
1024 bytes expanded to 1171 MIDI bytes in “packed MS bit” format
End of Exclusive (EOX)
Global Parameters Data Dump
Value
1111 0000
0000 0001
0010 1110
0000 1111
0vvv vvvv
1111 0111
Description
System Exclusive (SysEx)
DSI ID
OB-6 ID
Main Parameter Data
50 nibbles (LS then MS) for 25 Global parameters
End of Exclusive (EOX)
The Global Parameters Data Dump is not recognized when received; it is only transmitted when requested. NRPN messages are used to change Globals.
82 Appendix C: MIDI Implementation
Dave Smith Instruments
Packed Data Format
Data is packed in 8 byte “packets”, with the MS bit stripped from 7 parameter bytes, and packed into an eighth byte, which is sent at the start of the 8 byte packet.
Example:
Input Data Packed MIDI data
1 A7 A6 A5 A4 A3 A2 A1 A0
2 B7 B6 B5 B4 B3 B2 B1 B0
3 C7 C6 C5 C4 C3 C2 C1 C0
4 D7 D6 D5 D4 D3 D2 D1 D0
5 E7 E6 E5 E4 E3 E2 E1 E0
6 F7 F6 F5 F4 F3 F2 F1 F0
7 G7 G6 G5 G4 G3 G2 G1 G0
1 00 G7 F7 E7 D7 C7 B7 A7
2 00 A6 A5 A4 A3 A2 A1 A0
3 00 B6 B5 B4 B3 B2 B1 B0
4 00 C6 C5 C4 C3 C2 C1 C0
5 00 D6 D5 D4 D3 D2 D1 D0
6 00 E6 E5 E4 E3 E2 E1 E0
7 00 F6 F5 F4 F3 F2 F1 F0
8 00 G6 G5 G4 G3 G2 G1 G0
This explains why it takes 1171 MIDI bytes to transmit 1024 Program data bytes.
OB-6 Operation Manual
Appendix C: MIDI Implementation 83
84 Appendix C: MIDI Implementation
Dave Smith Instruments
DSI-10139R
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