Yamaha PM-2000 Owner's manual

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INTRODUCTION
INPUT MODULE
MASTER MODULE
- FOLDBACK/PHONE MODULE
EFFECTS MODULE
TALKBACK MODULE
MIX MATRIX.
REAR PANEL
POWER SUPPLY
METER PANEL . .
SPECIFICATIONS .
GENERAL .
INPUT CHARACTERISTICS
OUTPUT CHARACTERISTICS .
INSTALLATION
POWER MAINS .
THEORY OF GROUNDING .
INTERCONNECTIONS
PADS, TRANSFORMERS & DIRECT BOXES .
DYNAMIC RANGE
OPERATING LEVELS
GAIN OVERLAP & HEADROOM .
CALCULATING & USING GAIN OVERLAP
INTERFACE WITH CREATIVE AUDIO EQUIPMENT .
ADDING AN ADDITIONAL 10dB OF GAIN TO THE PM-2000 OUTPUT STAG ES
APPENDIX .
MAINTENANCE
TRAVEL CASE .
APPLICATIONS
CONCERT SOUND REINFORCEMENT .
STAGE MONITORING , .
TELEVISION SHOW PRODUCTION .
TELEVISION REMOTE PRODUCTION .
THEATRICAL PRODUCTION .
RECORDING & MIXDOWN . д...
BLOCK DIAGRAM. . . . . . . . . ."'.
© © 00 1 ос сл HOW
INTRODUCTION
-PM-2000 MIXING CONSOLE
In 1974 Yamaha set new standards of excellence for
sound reinforcement with the introduction of our first
PM-1000 mixing console. Since then, PM-1000’s have
been used by virtually every major sound company, and
praised by top artists around the world. PM-1000 consoles
enjoy a well-earned reputation for reliably delivering the
sound and mixing flexibility necessary in today’s creative
performances. | |
We were pleased by the success of our PM-1000, but
viewed it only as a beginning. The need for an even more
sophisticated Yamaha console became apparent, so for
the last 5 years we surveyed the professional sound
community in depth, learning which features are
considered most important. At the same time, new
circuits were devised, circuits capable of even better
performance than the already -respectable PM-1000.
Every detail, including panel layout and cabinetry,
received careful scrutiny. The goal was nothing less than
a total mixing system, one suitable for concert sound
reinforcement, theatrical or broadcast production, and
recording — it would become known as the PM-2000
mixing console.
We subjected the PM-2000 to an extended program of
rigorous laboratory and field testing, calling upon top
experts in every facet of the U.S. audio industry to
evaluate prototypes and work out improved designs.
When prototype consoles satisfied the most stringent
criteria on the lab bench and in studio evaluations, we
sent them out on numerous national and international
tours for “hands-on” evaluation. Here PM-2000’s received
a two year shake-down, the most valid of field tests.
Yamaha's stress on “real world” research and develop-
ment was an expensive but worthwhile investment that
had a major impact on the new console’s character. It
was a very special kind of R&D which relied upon close
communication with the touring soundmen and
engineers. We took the opportunity to discover any
latent difficulties (“if only they”d have ...”) in time to
avoid them. You showed us what was needed. We
supplied the intense research and the in-depth resources
to make it happen — the Yamaha PM-2000!
When you sit down to mix on a PM-2000 it commands
your respect. Yet for all its complexity and sophistica-
tion, you'll find the console’s layout uncluttered and its
functions self-explanatory; mixing with a PM-2000 comes
naturally. The PM-2000 somehow imparts immediate
confidence to any operator, and comfortable familiarity
to anyone who already knows the PM-1000. Controls
are well marked, sensibly organized, and perfectly
damped to respond to your most subtle touch.
Before long, you become aware of a very special
feeling. It is a feeling of elegance, of authority, of
control. As your eyes scan this impressive mixing console,
you see banks of large VU meters glowing clearly above
anti-glare black panels that are punctuated by color-
coded knobs, illuminated channel-ON switches, and the
occasional red flash of an input’s LED peak indicator.
Every so often an LED lights up in an otherwise tame
output VU meter, warning that the instantaneous level is
approaching a clip, but with +24dBm output capability
the console is seldom driven to its maximum. You
wonder what it is about the PM-2000 that gives you a
rush of enthusiasm. Could it be the rich rosewood
housing? Or is it simply that everything you need is at
your fingertips, beckoning to your creative instincts?
Whatever the reason, you understand why this console
is in a class by itself.
~ No, you are not beguiled. The PM-2000 is the ultimate
tool for creative audio mixing. Whether you choose the
compact 24 input mainframe, or the 32 input version,
you get 14 mixing buses, 4-knob 20-frequency equalizers,
switchable pre/post take-off for effects and monitor
sends, interstage patching, headphone cue and talkback
systems, a combination oscillator/pink noise source, and
more. Much more, in fact, because each of these features
is extraordinary by itself.
Take the equalizer, for,example. Four knobs each
provide 15dB of boost or cut at 5 frequencies, a total of
20 frequencies in overlapping ranges. The LOW and
HIGH EQ ranges have shelving curves for broad tonal
corrections, while the LOW-MID and HIGH-MID ranges
offer peaking characteristics for more exacting manipulia-
tion of the program. The controls are center-detented so
it's easy to return to a “flat” setting, and are center-
tapped so “flat” is absolutely flat. Of course, an
EQ IN/OUT switch facilitates A-B comparisons or fast
changes in tonal balance. The equalizer is an active
design with precision R-C networks and operational
amplifiers. We also provide a separate 18dB/octave High
Pass Filter with 40Hz and 80Hz positions, so you don’t
have to use the equalizer to eliminate unused low
frequencies or avoid problem sounds like wind noise,
stage rumble, dropped mics, vocal P-pops, etc.
Of the 14 mixing busses, 8 are designated for main
program mixing, 4 for foldback (stage monitoring), and
2 for echo/effects sends. Each bus has its own master
control, making it easy to pre-mix different “scenes,” to
instantly move from one type of mix to another, or to
quickly re-balance sub-groups of instruments, vocals and
effects. In addition to all this, the PM-2000 has a unique
mix matrix. |
The matrix allows the 14 mixing busses, plus auxiliary
inputs, to be combined into 8 discrete mixes. Each of
the 8 matrix mixes has its own master control, channel
ON/OFF switch, and appears at a direct console output.
You can use the main program outputs to make a “dry”
tape recording, while feeding the sound reinforcement
system with the matrix output; any desired effects can
be introduced to the matrix via its auxiliary inputs. The
matrix can save a tremendous amount of time and effort
when you want to set up individual stage monitor mixes,
feed different speaker mixes to various zones of the
house, feed local and remote programs simultaneously,
monitor in stereo during multi-channel recording, etc. —
all this, with no need for special patching or outboard
submixers.
The PM-2000 is built with only the finest components,
including low-noise mic preamps and accurate faders.
Electronically, all circuitry is designed for low noise, low
distortion and maximum stability; residual output noise
. is below —90dBm, and even at full +24dBm output level,
the IM and harmonic distortion remain unmeasurable on
all but the most sensitive equipment. Unwanted hum
(and heat) are excluded by using a remote power supply,
linked to the, PM-2000 by a detachable “umbilical cord.”
Not only is the console quiet internally, it also rejects
external noise. Balanced or floating inputs and outputs
block common-mode noise, while extensive shielding
and bypassing provide immunity to RFI (radio
frequency interference). | |
That the PM-2000 is a genuine value, a shining
example of modern electronic and mechanical design, is
no accident. It is the direct result of Yamaha’s experience
in building thousands of professional mixers and consoles,
as well as power amplifiers, electronic crossovers, speaker
systems, etc. The PM-2000 is perhaps even more of a
value due to Yamaha's diverse, worldwide manufacturing
resources: lumber mills (for wood cabinetry), foundries
(for metal parts), and semiconductor factories (for
transistors and IC chips). Because the unit is one of the
most reliable products on the market, is a state-of-the-
art design, and is backed by Yamaha, the PM-2000 will
retain its value for years. Thus, when you buy a
PM-2000, you are making a good investment — in terms
of resale value, day-to-day performance, and the satis-
faction that comes from owning the ultimate mixing -
console.
INPUT MODULE
A. PHASE switch inverts the polarity of the audio signal entering the input module,
eliminating the need for adapters or connector rewiring.
B. PHANTOM POWER switch applies 48V DC across the channel input connector’s
balanced signal leads and the cable shield: for remote powering of condenser
microphones. °
C. PROGRAM ASSIGN pushbuttons apply the channel output to any combination
of the 8 main mixing busses; a bright color shows when the button is engaged.
—D. PAN POT adjusts the relative output level between all odd-numbered and even-
numbered program mixing busses which have their Program Assign buttons engaged.
~ E. PAN ON/OFF pushbutton actuates the Pan Pot function.
~ F. EQ ON/OFF pushbutton bypasses or inserts the channel equalizer for rapid
E changes between “flat” and “EQ”d” sound.
E. G. EQUALIZER has 4-knobs that each provides 15dB of boost or cut, with center
д К detent at “flat” (no EQ) position. A concentric lever switch on each knob selects
a Ga the frequency band affected, as indicated below:
LO MID S
LOW range = 50, 100, 200, 350 or 500Hz (Shelving)
LOW-MID range = 250, 350, 500, 700 or 1,000Hz (Peaking)
HIGH-MID range = 0.8, 1.2, 2, 3.5 or 5kHz (Peaking)
HIGH range = 3.5, 5, 7, 9 or 12.5kHz (Shelving)
H. HIGH PASS FILTER pushbuttons allow for flat response when OFF, but may be
switched to cut frequencies below 40Hz or 80Hz at the rate of 18dB/octave, a
sharper cutoff than the EQ. The filter is useful for avoiding unwanted rumble and
pops, protecting speakers, etc.
3 93
[. ECHO knobs provide for two separate echo, effects, or monitor mixes. Adjacent
PRE/POST switches determine whether the pick-off comes before or after the
channel Fader (the PRE-Fader pick-off is factory wired to come after the EQ, but
can be moved ahead of the EQ by restrapping a jumper within the module).
J. FOLDBACK knobs provide for four separate foldback, monitor or effects mixes.
PRE/POST switches adjacent to each pair of knobs determine whether the pick-off
comes before or after the channel EQ and Fader (the PRE-EQ & Fader pick-off may
be changed to come after the EQ by restrapping a jumper within the module).
K. INPUT LEVEL switch determines the nominal channel sensitivity. By varying the
| preamplifier gain and/or attenuating the incoming signal, this switch preserves
: maximum headroom and minimum noise at each of 11 settings: —60, —50, —44,
BR | —38, —32, —26, —20, —14, —8, —2 and +4dB (Re: 0.775V).
EST L. PEAK indicator LED turns ON whenever the post-EQ, pre-Fader signal level
En reaches 3dB below clipping. This permits the Input Level switch to be quickly
Ш adjusted for the highest sensitivity that still preserves full headroom. With levels
properly set, the LED does not normally flash, but it will warn the operator if
too much equalizer boost i is applied or if the program level becomes excessive.
M. CHANNEL ON/OFF pushbutton removes the incoming program from all channel
outputs when OFF. This is particularly handy for rapid punch-ins, and punch-outs,
or for temporarily killing a channel without disturbing any of its mix levels. The
button is illuminated to let the operator know the channel is ON.
~ N. FADER travel is smooth and provides dB-calibrated attenuation. Integral seals in
the slider keep out dust and dirt.
O. CUE pushbutton assigns the post-EQ, pre-Fader signal to the cue bus and triggers
a relay in the Foldback/Phone module. The relay substitutes the cue bus for any
other busses assigned to the headphone jacks so the channel(s) can be previewed
prior to raising the Fader, Echo or Foldback controls. CUE also is useful for
identifying inputs, troubleshooting “bad” mics, etc. Individual channel CUE
buttons may be momentarily depressed or latched ON, displaying a bright color
when engaged; a “reminder” Cue LED in the FB/ Phone module also turns ON
whenever a Cue button is engaged.
NOTE: Inside this module are located a mic preamp, filter and EQ circuits, booster
and line amplifiers, and jumpers for pre-post EQ selection of echo and foldback
mixing busses. |
MASTER MODULE
MIX MATRIX SECTION*
A. ECHO 1 £ 2 controls pick off the signal from the two echo send output busses
A (after the Echo Send Master), assigning them to this one channel of the Mix Matrix.
В. FOLDBACK 1,2, 3 & 4 controls pick off the signal from the four foldback output
busses (after the Foldback Master controls), assigning them to this one channel of
the Mix Matrix.
C. PROGRAM 1, 2, 3,4, 5, 6, 7 € 8 controls pick off the signal from the eight
program output busses (after the Master Faders), assigning them to this one
channel of the Mix Matrix.
D. MATRIX MASTER control adjusts the overall mix level of any Echo, Foldback
and Program signals assigned to this one channel of the Mix Matrix, and hence sets
the level of the matrix output.
E. MATRIX ON/OFF pushbutton determines whether this channel of the Mix Matrix
is available to the headphone mix and the rear-panel matrix output connector.
This is particularly handy for rapid punch-ins, and punch-outs, or for temporarily
killing a matrix output without disturbing any of its mix level settings. The button
is illuminated to let the operator know when the Mix Matrix channel is ON.
F. AUXIN control adjusts the signal level applied to this one channel of the Mix
| Matrix from the correspondingly numbered Auxiliary Input. May be used to
© introduce effects into the Mix Matrix while keeping the program outputs “dry.”
MASTER OUTPUT SECTION
G. MASTER ON/OFF pushbutton turns the correspondingly numbered program
output ON or OFF. This is particularly handy for rapid punch-ins, and punch-outs,
or for temporarily killing an output without disturbing the Master Mix level. The
button is illuminated to let the operator know when the output channel is ON.
D
Ve H. MASTER FADER has smooth, dB-calibrated action, integral dust seals. Each
| Master Fader sets the level of the correspondingly numbered program output bus.
Ш Е I. CUE pushbutton assigns the pre-Master Fader signal to the cue bus and triggers a
relay in the Foldback/Phone module. The relay replaces whatever program had
been assigned to the headphone jacks with the cue bus signal, enabling the program
mix channel to be previewed without raising a Master Fader (no signal need be fed
to the program output). The CUE function also is useful for identifying mix
busses, troubleshooting, etc. Individual Master CUE buttons may be momentarily
F depressed or latched ON, displaying a bright color when engaged; whenever CUE is
engaged, an LED “reminder” in the FB/Phone module turns ON.
MATRIX CN/QFF
а]
| G NOTE: Inside this module are located the Aux Input transformer and line
WEI amplifier, the Program Output sum, booster and line amplifiers, and the Matrix
a Output line amplifier.
*There are a total of 8 Mix Matrix channels located in, and numbered to correspond
with, each of the 8 Master Modules.
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CUE
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FOLDBACK/PHONE
A
A. ECHO SEND | € 2 Master
“controls adjust the overall
echo output bus levels.
B. ЕОГОВАСК 1, 2, 3 & 4
. Master controls adjust the
, overall foldback output
bus levels.
C. HEADPHONE ASSIGN
pushbuttons select -
those signals mixed into
the headphone outputs:
Mix Matrix outputs 1
through 8, Echo Send out-
puts 1 and 2, and/or Fold-
back outputs 1 through 4.
Odd-numbered matrix out-
‘puts feed the Left muff and
even-numbered busses feed
the Right muff of any
stereo headphones plugged
into either of the two
headphone jacks. Echo and
Foldback outputs feed
both sides of the head-
phone output; these, and
any Mix Matrix Left and
Right phones signals are
summed (mono) for the
rear-panel phones output
XLR connector.
D. PHONES LEVEL control
adjusts the overall signal
level fed to both stereo
headphone jacks, and to
the mono phones con-
nector. |
E. CUE indicator LED turns
ON whenever a Cue
button is engaged on any
Input Module or Master
Module. This reminds the
operator that the head-
phones are carrying the
cue bus signal, not the
program selected with the
Headphone Assign push-
buttons (above).
NOTE: Inside this module are
located summing and line
amplifiers for the foldback,
echo and cue busses, as well
as the cue relay.
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EFFECTS
EFFECTS
MODULE
The following two clusters
of controls may be used for
processing an echo or reverb
return, as an assignable aux-
iliary bus input, and so forth.
EFFECTS IN #1 SECTION
A. PROGRAM ASSIGN push-
buttons apply the
EFFECTS INPUT #1
signal to any combination
of the 8 main mixing
busses; a bright color
shows when a button is
engaged.
B. ECHO & FOLDBACK
ASSIGN pushbuttons
apply the EFFECTS IN
#1 signal to any combina-
tion of the 2 echo and 4
foldback mixing busses.
C. EFFECTS IN #1 Level
control adjusts the level
of the incoming signal to
be applied to the mix
busses.
D. EFFECTS INPUT CUE
pushbutton assigns the
#1 Effects Input signal
(derived after the level
control) to the cue bus
and simultaneously triggers
a relay in the Foldback/
Phone module. The relay
substitutes the cue bus for
any other busses assigned
to the headphone jacks.
The Effects In signal thus
can be previewed prior to
switch-assigning it to the
various program, echo or
foldback busses. This CUE —
function also is useful for
listening to only the effects
portion of the program
during a mixing session. -
The CUE button may be
momentarily depressed or
latched ON, displaying a
bright color when engaged;
a “reminder” Cue LED in
the FB/Phone module also
turns ON whenever a CUE
- button is engaged.
EFFECTS IN #2 SECTION
E. This cluster of controls is
identical to the above, but
processes the signal from
EFFECTS INPUT #2.
NOTE: Inside this module are
located attenuation pads,
transformers, and booster
amplifiers for the two effects
input sections.
5
TALKBACK MODULE
A." PROGRAM ASSIGN pushbuttons apply the Talkback or Oscillator/Noise Generator
signal to any combination of the 8 main mixing busses; a bright color shows when an
Assign button is engaged. ‚
B. ECHO & FOLDBACK ASSIGN pushbuttons apply the Talkback or Oscillator/Noise
Generator signal to any combination of the 2 echo and 4 foldback mixing busses.
C. TB OUTPUT ON/OFF pushbutton applies signal to the rear-panel XLR Talkback
output connector, the Talkback VU meter and the LED peak indicator. Note that
when the TB OUTPUT switch is OFF, the module’s output can still be assigned to the
program, echo and foldback busses, even though the Talkback metering is inactive.
D. OSCILLATOR/NOISE GENERATOR pushbuttons offer a choice of sinewave signal
at 100Hz, 1kHz, or 10kHz, as well as pink noise. The Oscillator/Noise Generator may
be assigned to the busses as well as to a direct output, and is handy for signal tracing,
tape machine alignment, sound system setup, troubleshooting, and similar purposes.
The Oscillator/Noise Generator should be switched OFF when it is not in use.
E. LINE INPUT connector, a female XLR-3, accepts nominal —20dB (Re: 0.775V)
inputs for assignment to the program, echo and/or foldback busses. This connector
may be used for interface with popular 3-wire intercom systems, or for introducing
“background” or “intermission” music to the mix busses; the LINE INPUT will be
applied to any bus whose TB Assign pushbutton is engaged. The Line In signal only
appears at the Talkback output when the TB ON/OFF switch is ON.
F. LINE INPUT LEVEL control attenuates the level of signals applied to the Line Input
(decrease the setting of this control and TB LINE IN accepts +4dB nominal levels).
G. MIC INPUT connector, a female XLR-3, accepts nominal —50dB (Re: 0.775V) inputs.
This input is balanced and is ideal for interface with most low impedance (50 to
250 ohm) dynamic, ribbon or self-powered electret condenser microphones. The input
is activated by engaging the TB pushbutton; it is assigned to any of the program, echo
or foldback mixing busses selected with the module’s Assign pushbuttons, and/or to
the direct Talkback output. This input is useful for communication with technicians,
work crews and performers during system setup, for announcements, for control
room-to-studio communication, and for voice ID (“slating””) of tape recordings.
-— H. MIC INPUT LEVEL control adjusts the amplification of the Mic Input (may be ad-
justed up to —70dB sensitivity to accommodate lower level microphone signals).
I. TALKBACK (TB) pushbutton, when engaged, activates the TB Mic Input. When the
TB button is not engaged, the Oscillator/Noise Generator will feed any busses to
which the module is assigned (unless of course the Oscillator/ Noise Generator is
switched OFF). The TB button has no effect on the Line Input; both Mic and
Line sources may be assigned simultaneously. |
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NOTE: Inside this module are located mic and line input transformers, a mic preamplifier,
booster amplifiers, the oscillator and noise generating circuits, and a line amplifier.
MIX MATRIX
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MATRIX MASTER MATRIX MASTER MATI MASTER
MATRE ON/OFF MATRIX CNZOFE MATIN ON/OFF
The Mix Matrix is located on the upper
sections of the 8 Master Modules. Each
Master Module houses one channel of the
matrix, and can be used to create a dis-
crete mono combination from the con-
sole's 14 mixing busses. Each of the 8
matrix channels has the following controls
(discussed in greater detail in the Master
Module Description).
ECHO 1 & 2 level
FOLDBACK 1 — 4 level
PROGRAM 1 — 8 level
MATRIX MASTER level
MATRIX ON/OFF switch
AUX IN level
The 2 Echo, 4 Foldback and 8 Pro-
gram inputs to each matrix channel are
all derived after their respective bus
Master Faders. The 8 matrix channel out-
puts are available directly at rear panel
XLR connectors.
NOTE: When reading these matrix
application descriptions, refer also to the
sound system diagrams which follow
and to the fold-out console block diagram.
FOR SOUND REINFORCEMENT
The program, echo and foldback busses
may be used for sub-grouping of different
sources; i.e., brass, drums/percussion,
vocal backup, lead vocal, etc. The Mix
Matrix outputs are then used to feed
power amps (& speakers) for various zones
in the main house, the stage, and other
areas. With all Master Faders at nominal
settings, a basic balance of the sub-groups
can be established independently for each
zone of the sound system by using its
matrix channel.
There are a number of advantages to
this approach. For instance, if the brass
level is too high in all outputs, only one
Master Fader need be adjusted, and the
balance will simultaneously change in all
matrix outputs. For program fades, all
Matrix Masters may be brought down; the
previously established balance for each
zone of the sound system reappears as
soon as the Masters are again brought back
to nominal settings. Also, if any recordings
are being made directly from the program
outputs their fades need not follow the
house fades because the Matrix Master
controls do not affect the recording levels. |
The PM-2000’s foldback and echo
busses may be used for stage monitoring
when a separate monitor mixer is not
available. For more elaborate stage moni-
toring and simultaneous house mixing,
the PM-2000’s program outputs can feed
the house sound system, and the Mix
Matrix can create 8 different stage
monitor mixes.
FOR STAGE MONITORING
In a stage monitor console it is generally
desirable to obtain many different output
mixes. With the PM-2000 one could use
the 4 foldback outputs for 4 monitor
mixes. The 8 program busses could be
‘assigned as sub-groups and then combined
on the Mix Matrix to achieve 8 additional
monitor mixes. The echo send outputs
_ may be used for actual reverb send and
return, especially if the vocalist(s) enjoy
some reverb in the monitors; if not these
outputs provide additional monitor mixes.
At the same time, the sub-grouped pro-
gram outputs can be fed to the main
mixing console for incorporation in the
house mix. a
FOR RECORDING
When a multi-track tape recording is
being made, the 8 program bus outputs
can feed the recorder directly ; simul-
taneously, any two of the Mix Matrix
channels can be used to create a stereo
monitor mix (or four for a quad mix). 16-,
24- or 32-channel tapes can be made in
real time by using the interstage patch
outputs as direct channel feeds to the
recorder.
In some cases it is desirable initially to
make a “dry” recording, one without
echo or other special effects, but to
monitor the recording “wet”, with echo
or effects. This can be done simply by
connecting the echo/effects return line(s)
to the Mix Matrix auxiliary inputs rather
than to the console's effects inputs; the
Aux In level controls will then enable the
effects to be mixed into the monitors, but
since the tape machine is fed from the
master program outputs, it remains “dry.”
FOR TELEVISION PRODUCTION
For studio production work, the Mix
Matrix is helpful in creating mix-minus
feeds. These are sent to boom mic and
camera operators” IFB systems (inter-
ruptible foldback intercoms), as well as
to contestants or separated groups of
people who must not hear certain por-
tions of the program. The Mix Matrix also
proves useful in creating a full mono mix
of the show for a VTR feed (and the
soon-to-come stereo T.V. sound will be
easy to achieve using two Mix Matrix
channels). |
For remote production, pre-produc-
tion, or post-production work, the Mix
Matrix might best be used to feed various
VTR's with different audio mixes, to pro-
vide primary and secondary feeds to trans-
mission, or even to mix a reference tape
(mono or stereo cassette).
FOR THEATRICAL PRODUCTION
The typical production has several
scenes, each with different mic setups,
and some with special effects. If the pro-
gram busses are utilized to mix the differ-
ent scenes, each may be turned ON as re-
quired using the Master Program ON/OFF
switches. Each scene, however, will need —
to be fed to the various house speakers,
and this is where the Mix Matrix is very
useful. The 8 program busses can be
assigned to spread across the stage, across
audience fill channels, or into special
effects speakers. The Mix Matrix ON/OFF
switches may be used to activate the
“effects” speakers on cue. 7
REAR PANEL
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A. PHANTOM POWER MASTER switch turns the 48V
supply ON and OFF. When this switch is ON, 48V on
individual channels may still be turned ON and OFF
via front-panel switches. (41V for U.S. model)
— B. DC POWER INPUT connector accepts “umbilical”
power cable from remote supply.
C. MASTER GAIN switches change the overall gain of the
consolefrom normal to 10dB additional for 3 separate
circuits: ECHO, FOLDBACK and PROGRAM.
D. PROGRAM BUS OUTPUTS 1 through 8 are derived
from the 8 program mixing busses, after the Master
Faders.*
E. MATRIX OUTPUTS 1 through 8 are derived from the
8 Mix Matrix channels, after the Matrix Master controls.
F. PHONES OUTPUT is a mono blend of the stereo phones
mix developed in the Foldback/Phones module; output
level follows the setting for the stereo phone jacks.*
G. TALKBACK OUTPUT carries the Oscillator/Noise
Generator signal, TB program input, or TB mic input, .
depending on the switch status of the TB module. *
H. ECHO OUTPUTS 1 & 2 are derived from the 2 Echo
mixing busses, after the Echo Master controls. *
I. FOLDBACK OUTPUTS 1 through 4 are derived from
the 4 Foldback mixing busses, after the Foldback *
Master controls.
J. FOLDBACK MASTER PATCH POINTS 1 through 4
(IN and OUT jacks) come after the foldback mixing bus
summing amplifiers but ahead of the Foldback Master
“controls; nominal level is —6dB (Re: 0.775V).**
K. ECHO MASTER PATCH POINTS 1 & 2 (IN and OUT
jacks) come after the echo mixing bus summing
. amplifiers but ahead of the Echo Master controls;
nominal level is —6dB (Re: 0.775V).**
L. PROGRAM MASTER PATCH POINTS 1 through 8
(IN and OUT jacks) come after the program mixing bus
summing amplifiers but ahead of the program Master
Faders; nominal level is —6dB (Re: 0.775V).**
PM-2000-24
M. EFFECTS INPUTS 1 & 2 apply signal to the two effects
return channels in the Effects module, #**
N. AUX INPUTS 1 through 8 apply signal to corresponding-
ly numbered Mix Matrix channels via the Aux Level
controls, #**#
O. ECHO SUB INPUTS 1 & 2 apply signal directly to the
echo mixing busses (ahead of the Master Patch points
and Master Level controls). ***
P. FOLDBACK SUB INPUTS 1 through 4 apply signal
directly to the foldback mixing busses (ahead of the
Master Patch points and Master Level controls). ***
~ Q. PROGRAM SUB INPUTS 1 through 8 apply signal
directly to the program mixing busses (ahead of the
Master Patch points and Master Faders).***
R. INPUT MODULE INTERSTAGE PATCH POINTS
1 through 32 (or 24). The OUT jacks are post-EQ, and
the IN jacks Pre-Fader; nominal level is +4dB
(Re: 0.775V).**
S. CHANNEL INPUTS 1 through 32 (or 24) apply signal
to correspondingly numbered input modules. The
nominal level may vary from —60 to +4dB (Re: 0.775V),
depending on the setting of individual Input Level
switches. ***
*Connectors are balanced (floating) male ALR- 3, nominal +4dB
(Re: 0.775V) output level.
* **T.R. S. phone jacks for OUT and IN are wired in a
“normalled” configuration; i. e., so long as the IN jack is not
used, the OUT jack is internally wired to it for signal con-
tinuity. The OUT jack may be used as a direct output with-
out interrupting signal flow through the console. *
***Connectors are balanced (floating) female XLR-3,
nominal +4dB input level (Re:0.775V) unless otherwise
noted. |
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A. ON/OFF Switch This alternate-action pushbutton
turns the PM-2000 ON and OFF. —
B. POWER Indicator Lamp This red lamp is ON when
the PM-2000 power switch is ON.
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PIN| OUTPUT FUNCTION
2 | Ground. | Power Supply
3 Ground Chassis Ground
4 +24.5V Reg. For Most
5 —24.5V Reg. of the
7 Ground Console's
12 Ground Amplifiers
6 | +48V (+41V*) For Phantom Power .
13 +10V For Meter
14 Ground Lamps
8 +16V For Channel, Program
9 Ground & Matrix Switch Lamps
10 +24V | For Headphone Amp,
11 Ground Relay 8: Peak Indicators
15 _ _ |
16
*For U.S. model.
METER PANEL
A. AC POWER CORD This 3-wire (grounded) power
cordis for connection to suitable 50 or 60HZ AC
power mains: 120V RMS nominal for U.S. and
Canadian models, and other models with selectable
voltages of 110, 130, 220 or 240V RMS.
B. UMBILICAL CONNECTOR This multi-pin connector
mates the “umbilical” cable which brings power from
this supply to the PM-2000 console itself. A twist-
lock ring keeps the cable in place until you wish to
disconnect it.
C. AC LINE FUSE This fuse protects the primary side
of the power supply transformer. If a fuse blows,
replace it only with one of the same type and
current rating. Repeated fuse failure suggests a
fault which requires correction; do not attempt to
bypass the fuse as this may permanently damage the
power supply and/or the console, and will void the
warranty.
LARGE VU meters (#1 through #8) may be
individually switched to indicate the level of corres-
pondingly numbered PROGRAM Outputs or MATRIX
Outputs. The meters are illuminated, have true VU
ballistics, and are calibrated so that 0VU represents a
+4dBm (1.23V) output.
Four SMALLER VU meters each may be switched to
indicate the level of the 4 FOLDBACK Outputs or the
ECHO 1, ECHO 2, CUE and TALKBACK Outputs. The
meters are illuminated, have true VU ballistics, and are
calibrated so that'0 VU represents a +4dBm (1.23V)
“output. |
SPECIFICATIONS
GENERAL SPECIFICATIONS
10]
Frequency Response |
+0, —3dB, 20Hz to 20kHz; +0.5dB, 50Hz to 15kHz.
Total Harmonic Distortion
Less than 0.5% at +10dB* output, 20Hz to 20kHz;
Less than 0.1% at +20dB* output, SOHz to 20kHz
(rising to less than 0.5% at 20Hz).
Typically less than 0.3% at +20dB output, 20Hz to
20kHz, and less than 0.03%, 50Hz to 20kHz.
Hum & Noise** (20Hz to 20kHz, input termination of
150 ohms, all output assign switches ON, Input Level
switches at “—50”)
—128dBm Equivalent Input Noise.
—90dB* residual output noise: all Faders down.
78dB PROGRAM OUT Signal-to-Noise ratio, Master
and one Input Fader € nominal level.
81dB MATRIX OUT Signal-to-Noise ratio, Matrix mix
and Master controls @ maximum level, all Master
Faders and one Input Fader @ nominal level.
77dB FB or ECHO OUT Signal-to-Noise ratio, Master
level control and one FB or ECHO mix control @
nominal level.
Maximum Voltage Gain (Input Selectors at “—60dB,”
where applicable; rear-panel Gain Switch can add 10dB
more gain.)
84 +2dB, CHANNEL IN to PGM OUT;
84 +2dB, CHANNEL IN to MATRIX OUT;
84 +2dB, CHANNEL IN to FB OUT;
84 +2dB, CHANNEL IN to ECHO OUT;
10 +2dB, PGM SUB IN to PGM OUT;
20 +2dB, EFFECTS IN to PGM OUT.
Channel Equalization (+ 15dB maximum)
LOW: 50, 100, 200, 350, 500Hz (shelving characteristic);
LOW-MID: 250, 350, 500, 700, 1000Hz (peaking
characteristic);
HIGH-MID: 0.8, 1.2, 2, 3.5, SkHz (peaking
characteristic);
HIGH: 3.5, 5, 7, 9, 12.5kHz (shelving characteristic).
High Pass Filter
18dB/octave roll-off below 40Hz or 80Hz at —3dB points.
Oscillator/Noise Generator
Switchable sine wave @ 100Hz, 1kHz or 10kHz (1%
T.H.D. @ +4dB* output), or pink noise, **#*
Talkback
- Microphone input XLR, mic preamp, mic level control,
and push-to-talk switch, ***
Line input XLR, preamp, line level control. ***
~ Inputs & Outputs
(See accompanying tables of “Input Characteristics”
and “Output Characteristics.)
Crosstalk
—60dB @ 1kHz, adjacent inputs;
—60dB @ 1kHz, input to output.
VU Meters (0 VU = +4dB* output) |
8 large, illuminated meters; switchable for Program or
Matrix busses.
4 smaller, illuminated meters: all are switchable to
Foldback busses, 2 to Echo, 1 to TB and 1 to Cue bus.
Peak Indicators
LED built into each input module turns ON whefi the
pre-Fader level reaches 3dB below clipping.
LED built into each VU meter turns ON when post-
Master Fader level reaches 10dB below clipping.
Phantom Power
48V****DC is applied to balanced input transformers
(via 6.8 kohm current-limiting/isolation resistors) for
powering condenser microphones; may be turned ON
or OFF via rear-panel phantom Master switch. When
Master is ON, individual channels may be turned ON
or OFF via Phantom power switches on each input
module.
Finish
Black anodized aluminum panels, padded armrest,
rosewood veneer cabinet.
Dimensions
24-channel: 127.7cm wide (50-1/4”);
32-channel: 155.3cm wide (61-1/4”);
either unit: 102.3cm deep (40-1/4”)
x 40.3cm high (15-3/4”),
Weight
24-channel: 146kg (322 pounds);
32-channel: 170kg (375 pounds).
Power Consumption
24-channel: 240 watts:
32-channel: 270 watts.
Accessories
Integral carrying handles, removable leatherette cover,
PW-2000 power supply, and power supply DC inter-
connecting cable are all included with the console.
POWER SUPPLY (PW-2000) SPECIFICATIONS
. ****441V for U.S. model.
AC Line Voltage
120V RMS nominal (U.S. and Canadian models):
110, 130, 220 or 240V selectable (other models).
50 or 60H.
DC Output Voltages
+24 V (for preamps, buffer amps, and line amps);
+48V (for phantom mic power)**%*
+24V (for headphone amp, relay, and peak indicators);
+16V (for module lamps);
+10V (for VU meter lamps).
Finish
Black anodized aluminum; |
Front panel is designed for standard 19” rack mounting.
_ Dimensions (W x H x D)
48 x 14 x 33.7cm (19 x 5- 517 X 13- 1/4”).
Weight
15kg (33 pounds).
*0dB is referenced to 0.775VRMS (OdBm @ 600 ohms).
**Hum and Noise are measured with a 6dB/octave filter at 12.47
kHz; equivalent to a 20kHz filter with infinite dB/octave .
attenuation.
***Oscillator/Noise Generator and Talkback circuitry slates onto
the Program, Foldback and Echo busses. The TB ON/OFF
switch applies signal to the TB output XLR.
Specifications subject to change without notice.
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800, 1.2K, 2K, 3.5K, bK
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High Pass Filter Characteristics
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INPUT CHARACTERISTICS
Input Level*
Connection Bus Switch Impedance "Nominal Sensitivity ™¥ Nominal Max. Before Clip Consola"
—60 1 kohm —80dB (0.08mV) | —60dB (0.78mV} | —40dB (7.8mV)
—50 1 kohm —70dB (0.25mV) | —50dB (2.5mv) | —30d8 (25mv)
—44 1 kohm - —64dB (0.49mV} | —44dB (4.9mV) | —24dB (49mV)
—38 1 kohm 50 to 280 ohm | —2898 (0.98mV) | —38dB (9.8mV) | —18dB (98mV) В
CHANNEL 1-24 —32 1 kohm microphones —52dB (1.93mV) | —32dB (19.3mV) | —12dB (193mV)
INPUTS 1 — 32 —26 1 kohm 600 ohm —46dB (3.9mv) | —26dB (39mV) | —6dB (390mV) | XLR-3-31
—20 1 kohm sources —40dB (7.8mV). |-—20dB (78mv) | 0dB (780mV)
—14 | 1.7 kohms —34dB (16.5mV) | —14dB (155mV) | +6dB (1.55V)
—8 2.6 kohms —28dB (31mV) {| —8dB (310mV) | +12dB (3.1V)
—2 3.1 kohms —22dB (61.6mV} { —2dB (616mV) | +18dB (6.2V)
+4 3.3 kohms —16dB (123mV) | +4dB (1.23V) +24dB (12.3V)
AUX IN 1—8 5 kohms 600 ohm lines —6dB (390mV) +4dB (1.23V) +24dB (12.3V) XLR-3-31
EFFECTS IN 1,2 5 kohms | 600 ohm tines —16dB (123mV) | +4dB (1.23V) +24dB (12.3V) XLR-3-31
PGM SUB IN 1—8
FB SUB IN 1—4 1 kohm 600 ohm lines —6dB (390mV) | +4dB (1.23V) +24dB (12.3V) XLR-3-31
ECHO SUB IN 1,2 |
TB MIC IN 1 kohm 50 to 250 ohm mics | —70dB (0.25mV) |-50d8 (2.5mV) | —28d8 (31mv) | XLR-3-31
TB LINE IN 5 kohms 600 ohm lines —40dB (7.8mV) —20dB (78mV) +2dB (980mV) XLR-3-31
CH PATCH IN |1-240r32 1.3 kohms ‘| 600 ohm lines —16dB (123mV) | +4dB (1.23V) +24dB (12.3V) TRS Phone Jack
PGM PATCH IN | 1-8
FB PATCH IN 1—4 10 kohms | 600 ohm lines —16dB (123mV) | —6dB (390mV) | +24dB (12.3V) TRS Phone Jack
ECHOPATCHINI 1,2 |
OUTPUT CHARACTERISTICS
c i Chan/ | Actual Source For Use With Output Level* Connector In
onnection . * +
Bus Impedance Nominal Nominal Max. Before Clip Console
PGM QUT 1—8
MATRIX OUT 1—8 |
FOLDBACK OUT 1—4 150 ohms 600 ohm lines +4dB (1.23V) +24dB (12.3V) XLR-3-32
ECHO OUT 1,2
TB OUT
CH. PATCH OUT 1—240r32| 600 ohms 10 kohm lines +4d8 (1.23V) +24dB (12.3V) TRS Phone Jack
PGM PATCH OUT 1-8
FB PATCH OUT 1-4 600 ohms 10 kohm lines —6dB (390mV) +24dB (12.3V) TRS Phone Jack
ECHO 1,2 |
PATCH OUT N
PHONES OUT 150 ohms 600 ohm lines +4d8 (1.23V) +24dB (12.3V) XLR-3-32
HEADPHONES 1, 2 33 ohms | 8-ohm phones —4dB (489mV) +6dB {1.55V) TRS Phone Jack
; 600 ohm lines +10dB (2.45V) +20dB (7.8V)
*OdB is referenced to 0,775V RMS.
**All XLR connectors are floating (balanced channel inputs) and transformer-isolated. TRS phone jacks are unbalanced, with separate
audio common and chassis ground connections (except headphone jacks, wired Tip=Left, Ring=Right, Sleeve=Common).
1Sensitivity is the level required to produce a nominal output of +4dB8 (1.23V) or the specified nominal output level ¡f other than +4dB.
NOTE: SENSITIVITY MAY BE INCREASED ANOTHER 10dB by rear-panel Gain Switches (except for Aux In).
REGARDING DESIGNATION OF INPUT & OUTPUT LEVELS
In these specifications, when dB represents a specific
voltage, OdB is referenced to 0.775V. “dB” is a voltage
ratio, whereas “dBm” is a power ratio. 0dBm is referenced
to 1 milliwatt (0.775V RMS driving a 600-ohm termina-.
tion). For example, when 12.3V is.fed to a high imped-
ance, the level is designated “+24dB”. When +24dB
(12.3 volts) drives a 600-ohm termination, the level is
designated “+24dBm” (250 milliwatts).
If the voltage remains the same when the termination
changes, the power level changes; +24dB (voltage) driving
‚а 300-обт termination would be +27dBm (500 milli-
watts), and +24dB driving a 150-ohm termination would
be +30dBm (1 watt). The signal voltage level in “dB” is
specified, wherever applicable, (1) to avoid confusion
about levels when the mixer is connected to various low
impedance of unknown impedance, and (2) to be more
accurate in specifying voltage levels across high impedance
circuits. |
POWER MAINS
U.S.A. and Canadian models are designed to operate
from 110 to 120V AC, 50 or 60Hz power mains.* The
mixer must be AC grounded for safety and for proper
shielding; a 3-wire power cable is provided for this
purpose. If a 3-wire outlet is not available, or if there
is any chance the outlet may not be grounded, a separate
jumper wire must be connected from the mixer chassis to
an earth ground. Cold water pipes generally provide good
grounds, although if they are insulated by a length of
PVC pipe or a water meter, cold water pipes are not
good grounds. (An electrical wire bypasses some meters,
supplying ground continuity for the cold water pipes.)
Avoid hot water pipes and gas pipes. When in doubt, use
a length of copper pipe driven into moist, salted earth,
burying at least 1.5m (5 ft) of pipe. Alternatively, use
one of the new chemical type ground rods.
Connect the mixer to the power mains ONLY AFTER
CONFIRMING THAT THE VOLTAGE AND LINE
- FREQUENCY ARE CORRECT. (By all means, USE A
VOLTMETER ... it can save your equipment and the
show.) It is also a good idea to check for proper polarity
in the AC outlet. The Power Switch on the mixer should
be Off and the “umbilical” cable disconnected before
connecting the console to the mains. As a precaution,
disconnect the console from the mains while audio cables
are being installed.
CAUTION: Severe over voltage or under voltage in the
power mains can damage the console's circuitry. Always
check the AC line before connecting the mixer's AC
power cable. Use an RCA Power Line Monitor, or any
suitable AC voltmeter. The power line must measure
more than 105V AC and less then 130V AC (rms). Some
lines are “soft,” meaning that the voltage drops when
the line is loaded due to excessive resistance in the
power line. To be certain the voltage is adequate, check
it again after turning on the console, and any power
amplifiers that might be connected to the same power
mains.
If power line voltages do not fall within the 105V AC
to 130V AC range, do not connect the console to the
AC line. Do find a suitable line or contact a qualified
electrician. Failure to observe this precaution may
damage the console, and will void the warranty.
THEORY OF GROUNDING
Careful grounding procedures are essential for proper
operation, not only of the PM-2000, but of the entire
audio system. Many grounding techniques exist, and
certainly there are several ways to achieve a satisfactorily
grounded audio system. Several books have been
written on the subject. For further information (to
complement the information presented below), consult
the following sources: THE AUDIO CYCLOPEDIA by
Howard M. Tremaine (Pub. Howard W. Sams);
SOUND SYSTEMS by Don and Carolyn Davis
(Pub. Howard W. Sams); GROUNDING AND SHIELD-
ING IN INSTRUMENTATION by Ralph Morrison
(Pub. John Wiley & Sons).
WARNING: In any audio system installation, govern-
mental and insurance underwriters’ electrical codes must
be observed. These codes are based on safety, and may
vary in different localities; in all cases, local codes take
*Other power supplies are available for various power mains
throughout the world. Consult your Yamaha PM-2000 dealer.
precedence over any suggestions contained in this manual.
As set forth in the PM-2000 Warranty, Yamaha Inter-
national Corporation shall not be liable for incidental or
consequential damages, including injury to persons or
property, resulting from improper unsafe or illegal
installation or use of the PM-2000 or of any related
equipment; neither shall the Corporation be liable for
any such damages arising from defects or damage result-
ing from accident, neglect, misuse, modification, mis-
treatment, tampering or any act of nature. >
The following grounding scheme is presented in the
belief that it is one of the more simple, yet effective
methods available, but by no means is it the only
effective method.
Grounded loops (also called “hum loops”), are often
caused by multiple paths from equipment grounds to
the AC main ground (“earth” ground). Ground loops
tend to induce hum and allow noise to develop in an
audio system; in severe instances, equipment may begin
to oscillate due to ground loops. This oscillation can
cause distortion and even damage to amplifiers and loud-
speakers. One way to avoid ground loops is to make sure
that there is just one path to the AC ground (earth
ground) for the entire audio system.
The PM-2000 chassis provides a convenient point
from which all other equipment in the system can
derive its ground. First, isolate all auxiliary equipment
grounds (usually the chassis) from the AC main ground.
Then ground the auxiliary equipment (chassis) to the
PM-2000 chassis via the shields of the interconnecting
audio cables. To insure the success of this scheme, the
PM-2000 chassis itself must be well grounded, either
through the ground lead in its AC cable, or through an
earth ground attached to the mixer chassis.
Much of the auxiliary equipment sold today is
equipped with 2-wire AC power cables, which implies
that the equipment is isolated from the AC main ground.
If the equipment has a 3-wire AC cable, its chassis is
probably grounded to the power mains through the
rounded, center prong of the power plug; a 3-prong to
2-prong adapter may be used to interrupt that ground.
WARNING: When a chassis is not grounded directly to
the AC mains, it must be grounded to the PM-2000
chassis by the shields of interconnecting audio cables;
the PM-2000 thus links the remote equipment chassis
to the AC main (earth) ground. Should the shield of a
cable break (or in the event a cable is disconnected), it
is possible for dangerous potential differences (LETHAL
AC VOLTAGES) to develop between the remote chassis
and any other grounded device. Therefore, it is
extremely important when using this grounding scheme,
especially with guitar amplifiers, that continuity be
maintained between the remote chassis and the
PM-2000 chassis at all times, even when the power
switch is OFF.
As a precaution, test every chassis and microphone
case with an ohm meter to assure that it is grounded to
the power main (or earth) ground. In the previously
13
14
described grounding scheme, this can be accomplished
by confirming the PM-2000’s continuity to ground, and
then confirming that there is virtually no resistance
between the remote chassis and the PM-2000 chassis.
GROUNDING ON THE ROAD
Many of the above procedures are difficult to use on
the road. For example, the telescoping shield concept is
nearly impossible to use on a portable cable. Similarly,
it is a difficult and time consuming process to search for
a water pipe ground every time the system is moved
from one performance to another. Yet portable systems
can be extremely complex, and may have major ground-
ing problems.
The telescoping shield concept can be extended to
portable systems by installing a “ground lift switch” on
the output of each device, and on the inputs of devices
after the mixer. Since microphones are not grounded
except through the mixer, there is no need for an input
ground lift switch on most mixers. The diagram below
shows a typical ground lift switch installation. By
judicious use of these switches, each piece of equipment
~ can be AC grounded for safety without causing ground
loops.
Because of leakage currents from equipment in the
audio system, and in the house, some noise currents can
ride on the AC ground wire and are able to enter the
audio system. This problem is usually most noticeable
with sensitive equipment such as the mixer. Lifting the
AC ground at the mixer can often solve this problem.
However, lifting the AC ground on the mixer also lifts
the AC ground on the microphone chassis, causing a
safety hazard. Try connecting the mixer and any other
sensitive equipment to other AC circuits. The only other
apparent solution to this problem is to eliminate the
noise on the AC ground; which is not an easy task. Since
it has its own ground, a portable AC power distribution
system connected to the house service entrance may be
the most effective way to avoid all AC noises. Such a
system can be designed and constructed by a qualified
electrician; check local electrical codes before each use.
Devices with Balanced Inputs & Outputs
ern |
Cable with Shield Intact PS
e | [| x 1 1]
o— AJ ¿$
"Ground Lift
Switch Installed
in Box or on
Rack Panel
Main AC Ground
Use of Ground Lift Switch
Perhaps the best answer to portable system grounding -
problems, RFI, EMI, and AC noises, is to develop a
versatile grounding scheme. Ground lift switches and
adapters, and a portable AC power distribution system
allow different grounding techniques to be tried easily
and quickly when a problem occurs.
INTERCONNECTIONS
AUDIO CONNECTORS AND CABLE TYPES
The PM-2000 is fitted with only three types of audio
connectors: 3-pin XLR male, 3-pin XLR female, and
3-conductor standard phone jacks (stereo). .
2-conductor (twisted pair) shielded cable is best for all
XLR connections. Belden No. 8412, or its equivalent, is
an excellent cable due to its heavy construction. This
type of cable should be used for all portable applications.
A lighter duty cable, such as Belden No. 8451, or its
equivalent, is suitable for permanent installation, or for
permanently connected cables in portable racks. “Snake”
cables containing multiple shielded pairs must be
handled very carefully because the leads tend to be
fragile, and a broken conductor cannot be repaired.
If low level and high level lines, or if either of these
lines and speaker cables are run parallel for long distances,
crosstalk may be great. In fact, the crosstalk can cause an
electronic feedback loop, oscillation, and possible
damage to the equipment. To minimize crosstalk,
physically separate low level (microphone) cables from
high level (line) cables by the greatest feasible distance.
Keep speaker cables away from both low and high level
signal cables. At any point where cables meet, run low
level cables perpendicular to high level or speaker cables.
If low and high level or speaker cables must be run
parallel and in close proximity to one another, they
should be bundled separately. |
INTERFACE
The PM-2000 accepts balanced or floating input
sources directly, with no need for auxiliary transformers.
Most professional microphones, and most other low
impedance professional audio devices, fall in this
category Unbalanced, low impedance equipment can
also be connected directly to the input channels of the
PM-180, M-508, M512, M916 and M1516, with the
appropriate adapter cable (see the illustrations on the
next page).
NOTE: The XL connectors in Yamaha mixers are wired
to conform with DIN (European) standards, which
dictate that pin 2 is high, pin 3 low, and pin 1 the
shield connection. Given a positive signal at pin 1, it will
be in phase with a positive signal on the high side of one
of the mixers unbalanced outputs.
Use an auxiliary impedance matching transformer
(high impedance to low impedance) to connect a high
impedance source to the low impedance inputs of the
PM-2000. Transformers can also provide isolation
between balanced and unbalanced lines.
If an attenuation pad is required, always install it
on the high level side of the transformer (the source
side). This reduces the signal level passing through the
transformer, which tends to optimize the performance
of the transformer by avoiding magnetic core saturation.
REMOTE
MIXER CONSOLE
REMOTE
DEVICE — SIDE OF CABLE SIDE OF CABLE
DESCRIPTION — (Connector Type) CABLE (Connector Type)
11 WHT (RED)/HI
A. XLR
{XLR)
Floating or Balanced _— BLACK/LOW
low impedance: most SHIELD/GND
professional equipment
line in and tine out,
microphones,
Tu =, WHT (RED)/HI .
8. TRS т XLA
PHONE Ll BLACK/LOW (XLR)
5 SHIELD/GND
Unbalanced T. vey WHT {RED)/HI
low impedance: some C. STANDARD ai Do BLACK/LOW (XLR)
professional equipment "PHONE + “a
and microphones. : $ | SHIELD/GND
T - WHT/RED/HI
D. STANDARD — ; :
7 PHONE oc] qui BLACK/LOW (10° or less) : (XLR)
. $ SHIELD/GND
Unbalanced |?
high impedance: most
hi-fi equipment, t
> E. RCAPIN = WHT (RED)/HI
= os BLACK/LOW (10° or less) (XLR)
3 SHIELD/GND
{10° or less)
тои WHT (BLACK)/HI Pa „т
ONE Y oa ; SHIELD/GND \
Unbalanced $ =” - $
high impedance: most (10° or less) (STANDARD
hi-fi equipment. 6. RCA-PIN и WHT (BLACK)/HI NT PHONE)
; SHIELD/GND ‘ e
- 5
Connector and cable configurations recommended for use with the PM-2000. These cables
are based on the use of auxiliary equipment that is isolated from the AC power mains.
tt This wiring configuration {Pin 2 high, Pin 3 low) matches the
PM-2000 wiring and DIN standards. Much of the equipment
in the U.S.A. is wired with Pin 3 high and Pin 2 low (shield
is still Pin 1). In most cases involving the PM-2000, this makes
no difference. However, interconnections between other
manufacturer's equipment may require that Pins 2 and 3 be
reversed; consult the manufacturer's literature.
t Use this cable at remote equipment, and install matching
transformer with high-Z side toward remote equipment.
Then use cable À to join the low-Z side of the transformer
to the console. Use of the transformer at the high-Z
location allows long cable runs to the low-Z connection.
PADS, TRANSFORMERS
& DIRECT BOXES
ATTENUATION PADS
The most common professionally used pads are
“T-pads” and “H-pads.” T-pads unbalance true
balanced lines (and floating lines), but work well in
unbalanced circuits. H-pads are best for balanced or
floating lines, but should not be used in an unbalanced
circuit since they will insert a resistance in the return
lead (ground). For a discussion of other types of pads,
refer to the AUDIO CYCLOPEDIA by Howard M.
Tremain (Pub. Howard W. Sams).
Always install a pad near the input of the device
it feeds, with as short a length of cable as possible on
the low level side of the pad. This maintains a high
signal level in the longer transmission cable, reducing
the effects of any induced hum and noise.
The pads illustrated can be built for 600-ohm or high
impedance lines. Commercially manufactured pads are
available; consult your Yamaha dealer. When connected
between a 600-ohm (or lower) source and a 600-ohm
(or higher) termination, pad attenuation values will
remain fairly accurate. For higher impedance circuits,
resistor values must be changed. To obtain the correct
resistor values; multiply the values given for 600-ohm
pads by the output impedance of the source device,
and divide that answer by 600. The high impedance pad
values listed for the T-pads are close approximations of
average hi-fi pads, based on 10,000-ohm nominal
impedances. |
For low level circuits, use 1/4 watt resistors. For
— outputs with CONTINUOUS sine wave levels above
+24dBm, use 1/2 watt resistors; for CONTINUOUS sine
wave levels, above +30dBm, use 1 watt, low inductance
resistors. 10% tolerance is acceptable for most pads. It
is possible to construct a pad within an XLR connector,
but the extremely tight fit can adversely affect
reliability. The Switchcraft model S3FM is a tube with
a male XLR (A3M) at one end, and a female XLR
(A3F) at the other. Pads using 1/4 Watt resistors can
be constructed inside the S3FM. Cover the entire pad
with insulation tubing before final assembly into the
S3FM. |
A “mini-box” fitted with male and female XLR
connectors is an easy to build, rugged housing for a
pad. Use stranded wire for best results.
Illustrated on next page are two typical pad con-
struction techniques. For most applications, it will be
sufficient to construct only a few types of pads: 20dB,
24dB, and 40dB pads cover almost any requirements.
(Consult table on next page for schematic and resistor
value information.) |
15
DIRECT BOXES
dB Loss R1T (ohms) R1H (ohms) — R2 The term “direct box” refers to an adapter which
0.5 permits a power amplifier to drive a lower level input.
1.0 Direct boxes are often connected between the speaker
To output of an electric instrument amplifier and the input
4.0 of a mixer. By using the amplifier’s speaker output, the
5.0 reverb, tremolo, brightness, and other sound character-
6.0 . istics are conveyed to the mix. The standard direct box
29 consists of an attenuation pad that reduces the level,
9.0 and an impedance matching transformer to correctly
10 terminate the mixer’s input.
12 A T-pad combined with a matching transformer box
Le (described following this discussion) together make a
18 good direct box. Connect the T-pad between the trans-
20 former’s high impedance input and the speaker output
22 of the amplifier. Approximately 20-40dB of padding is
Se needed to prevent transformer saturation (the pad value
28 depends on amplifier power). Another 20dB (approxi-
30 mately) of voltage level is lost in the transformer due to
32 impedance matching.
de As a rough guide, a 40dB T-pad should be used with
38 amplifiers rated from 50 to 200 Watts (continuous sine
40 wave power), and the 20dB pad should be used for
50 smaller amplifiers. Small level variations are corrected
Attenuation Pad Construction and Resistor Values for with the mixer’s input level switches and faders. If the
High !mpedance (10k-ohm) and Low Impedance (600 ohm) instrument amplifier does not have a phone jack for the
[shaded area] circuits. speaker output, prepare a cable, as shown below, which
substitutes a pair of clips for the phone plug. Attach the
clips to the speaker terminals, and the XLR connector
to the T-pad. If humis a problem, try reversing the clip
leads on the speaker terminals.
A variation of the direct box just described, meant for
low levels, contains a “Y” adapter that enables it to be
inserted between the instrument and the amplifier. The
Y-adapter taps the instrument output and feeds it
through an impedance matching transformer into the
mixer.
This direct box variations can be assembled with the
impedance matching transformer box, described in the
following paragraphs, and with a special “Y”-adapter
cable. A further variation is the active direct box, an
| isolation amplifier that has a high input impedance, and
"ТОВАР HI is meant for insertion between the instrument and the
Ri Ri mixer. An excellent design for an active direct box
has been provided through the courtesy of Deane Jensen,
in cooperation with Westlake Audio. This unit is
described at the end of this section.
ts Be ed
i
O- —e O LO
MALE
XLR
BLACK WIRE
CLIP JUMPER
TO SPEAKER TO TPAD
OR AMP OUTPUT
TO INSTRUMENT'S ù . TO
“H” PAD. | AMPLIFIER INPUT A CENTER CONDUCTOR ~~ . XxPMA
STD PHONE E—— + T3} MALE
PLUG Pal! SHIELD Ly |. XLR
STD PHONE V «+
JACK 1 ob
Ч
FROM INSTRUMENT JUMPER
MATCHING TRANSFORMER BOX |
Impedance matching transformers are manufactured
by several firms. Use a transformer capable of handling
nominal +4dB (1.23V) inputs with at least +24dB
(12.3V) peak capability. (Alternately, use an attenuation
pad to drop the level ahead of the transformer.) Because
there is a voltage loss of about 20dB in the transformer,
due to impedance matching, the +4dB (1.23 volts).input
becomes about —6dB (0.123 volts) at the secondary. Set
the mixer’s Input Level Switch to —20dBm.
The transformer should have a primary impedance of
approximately 30,000 ohms, and a secondary impedance
of 600 ohms. For high impedance microphones, a
primary impedance of 50,000 ohms and a secondary of
150 ohms is preferable. A UTC-010 transformer with
the UTC-019 shield is acceptable for most applications;
equivalent transformers should have similar level
handling and impedance characteristics.
The transformer should be mounted in a mini-box,
wired to XLR connectors with stranded wire, and
connected to the auxiliary equipment with one of the
cables previously illustrated. In-line transformers, such
as those manufactured by Shure Brothers, Sescom, and
others may be used, with suitable adapters.
GUITAR DIRECT BOX (Passive)
The direct box diagrammed below represents an
improvement in performance over a direct box that
has been assembled from “‘off the shelf” components.
Its transformer, pad, filter, and grounding and shielding
arrangement have been specially designed for direct box
use. It is not a commercial product, however, and can
be assembled by any competent technician. If carefully
constructed, the direct box should work well with the
PM-2000. The design was included in this manual for the
benefit of the user of the PM-2000, and does not repre-
sent an endorsement by Yamaha of the specific products
mentioned.
The direct box can be used in three ways: 1. at the
output of a standard electric guitar, without an amplifier
(pad switch open, ground switched closed); 2. at the out-
put of a standard electric guitar with a guitar amplifier
also connected (pad switch open, ground switch open or
closed); 3. at the output of a guitar or instrument
amplifier or preamplifier (pad switched in, ground switch
open or closed). The filter switch, which only works
when the pad switch is closed, simulates the high
frequency roll off of a guitar amp speaker. Since clipping
distortion in a guitar amp creates high frequency
harmonics, the filter switch, by lowering high frequency
response, also cuts distortion.
The transformer was designed specifically for use in
FEMALE XLR
UTC-010
MALE XLR
or equivalent
6 1
21
3
6009
ROD
BOX GROUND LUG
Matching Transformer Box
a guitar direct box. When connected to a standard
electric guitar pickup, and a mic input on a PM-2000,
the transformer reflects the optimum load impedance
to both the guitar pickup and the mic preamp input
transformer. This maintains the frequency response and
transient response of both the guitar and the PM-2000.
The pad and filter were designed to maintain optimum
loading. The transformer has two faraday shields, to
prevent grounding and shielding problems that could
cause hum in the PM-2000 or the guitar amplifier. Place
the ground switch in which-ever position works best
(see the previous paragraph for suggestions).
Assembly can be similar to the matching transformer
box shown. Keep the phone jack isolated from the
chassis of the box and during operation, keep the chassis
of the box away from the chassis of the guitar amp or
any other grounded object. If you decide to use a trans-
former other than the Jensen model JE-DB-D, it should
have similar characteristics: an impedance ratio of
20k-ohms (primary) to 150-ohms (secondary), dual
faraday shields, very low capacitance primary winding,
and full audio spectrum frequency

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