Owner’s manual
RKB-2100
Power Amplifier
POWER
L
R
LEVEL
POWER AMPLIFIER RKB-2100
PROTECTION
Important Safety Instructions
WARNING: There are no user serviceable parts inside. Refer all servicing to qualified service personnel.
WARNING: To reduce the risk of fire or electric shock, do not expose
the unit to moisture or water. Do not expose the unit to dripping or splashing. Do not place objects filled with liquids, such as vases, on the unit. Do
not allow foreign objects to get into the enclosure. If the unit is exposed
to moisture, or a foreign object gets into the enclosure, immediately disconnect the power cord from the wall. Take the unit to a qualified service
person for inspection and necessary repairs.
Read all the instructions before connecting or operating the component.
Keep this manual so you can refer to these safety instructions.
Heed all warnings and safety information in these instructions and on the
product itself. Follow all operating instructions.
Clean the enclosure only with a dry cloth or a vacuum cleaner.
Do not use this unit near water.
You must allow a minimum 10 cm or 4 inches of unobstructed
clearance around the unit. Do not place the unit on a bed, sofa, rug,
or similar surface that could block the ventilation openings. If the unit is
placed in a bookcase or cabinet, there must be ventilation of the cabinet
to allow proper cooling.
Keep the component away from radiators, heat registers, stoves, or any
other appliance that produces heat.
The unit must be connected to a power supply only of the type and voltage
specified on the rear panel. (USA: 120 V/60Hz, EC: 230V/50Hz)
Connect the component to the power outlet only with the supplied power
supply cable or an exact equivalent. Do not modify the supplied cable. A
polarized plug has two blades, with one wider than the other. A grounding
plug has two blades plus a third grounding prong. These are provided for
your safety. Do not defeat grounding and/or polarization safety provisions.
If the supplied plug does not fit your outlet, please consult an electrician
for replacement of the obsolete outlet. Do not use extension cords.
This symbol means that this unit is double insulated.
An earth or ground connection is not required.
The main plug of the power cordset is a disconnect device of the apparatus. In order to completely disconnect the apparatus from the supply
mains, the main plug of the power cordset should be unplugged from the
mains (AC) outlet. The stand-by LED indicator will not be lit up to show
the power cord is unplugged.
Do not route the power cord where it will be crushed, pinched, bent, exposed to heat, or damaged in any way. Pay particular attention to the
power cord at the plug and where the cord exits the back of the unit.
The power cord should be unplugged from the wall outlet during a lightning
storm or if the unit is to be left unused for a long period of time.
Use only accessories specified by the manufacturer.
Use only with a cart, stand, rack, bracket or shelf system recommended
by Rotel. Use caution when moving the unit in a stand or rack to avoid
injury from a tip-over.
Use Class 2 wiring for speaker connections to ensure proper installation
and minimize the risk of electrical shock.
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POWER
L
R
������
LEVEL
POWER AMPLIFIER RKB-2100
PROTECTION
Immediately stop using the component and have it inspected and/or serviced by a qualified service agency if:
• The power supply cord or plug has been damaged.
• Objects have fallen or liquid has been spilled into the unit.
• The unit has been exposed to rain.
• The unit shows signs of improper operation
• The unit has been dropped or damaged in any way
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WARNING: The master power switch is located on the rear panel. The
unit must be located in the open area allowing unobstructed access to
the main power switch.
RKB-2100 Power Amplifier
4
1: Controls and Connections
1
2
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POWER
L
R
LEVEL
POWER AMPLIFIER RKB-2100
PROTECTION
WARNING:
TO REDUCE THE RISK
OF FIRE OR ELECTRICAL SHOCK,
DO NOT EXPOSE THIS EQUIPMENT
TO RAIN OR MOISTURE.
WARNING: SHOCK HAZARD—DO NOT OPEN.
12V TRIG
OFF
SPEAKERS
RIGHT
LEFT
OUT
IN
SIGNAL SENSE
RIGHT
LEFT
INPUT
RIGHT
LEFT
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SIGNAL OUTPUT
LINK
4 OHMS MINIMUM
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AC BREAKER
AVIS: RISQUE DE CHOC ÉLECTRIQUE—NE PAS OUVRIR.
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POWER AMPLIFIER
MODEL NO. RKB-2100
POWER CONSUMPTION: 450 W
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English
5
2: Hook-up Illustration
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WARNING:
TO REDUCE THE RISK
OF FIRE OR ELECTRICAL SHOCK,
DO NOT EXPOSE THIS EQUIPMENT
TO RAIN OR MOISTURE.
WARNING: SHOCK HAZARD—DO NOT OPEN.
12V TRIG
OFF
SPEAKERS
RIGHT
LEFT
OUT
IN
SIGNAL SENSE
RIGHT
LEFT
INPUT
RIGHT
AC BREAKER
AVIS: RISQUE DE CHOC ÉLECTRIQUE—NE PAS OUVRIR.
LEFT
4 OHMS MINIMUM
SIGNAL OUTPUT
LINK
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POWER AMPLIFIER
MODEL NO. RKB-2100
POWER CONSUMPTION: 450 W
RKB-2100 Power Amplifier
Contents
Important Safety Instructions .................. 3
1: Controls and Connections .................................4
2: Hook-up Illustration.........................................5
About Rotel ............................................ 7
Getting Started ....................................... 7
Features ..............................................................7
A Few Precautions................................................7
Placement ...........................................................7
Rack Mounting ....................................................7
Rack Handles ......................................................8
Optional Fan Kit
............................................8
AC Power and Control ............................ 8
AC Power Input
Power Switch
Indicator LED
.............................................8
.................................................8
Auto Turn On/Off Mode Selector
...................8
12V Trigger Input
.........................................8
12V Trigger Output
.......................................8
Circuit Breaker
.............................................8
Protection Indicator
.......................................8
Signal Connections .................................. 9
RCA Inputs
....................................................9
Input Level Controls
......................................9
Signal Output Link
........................................9
Speakers ................................................ 9
Speaker Selection ................................................9
Speaker Wire Selection ........................................9
Polarity and Phasing ............................................9
Speaker Connections
...................................10
Troubleshooting..................................... 10
Front Panel Power Indicator Is Not Lit .................10
No Sound ..........................................................10
Protection Indicator Is Lit ...................................10
Specifications ........................................ 10
6
English
7
About Rotel
A family whose passionate interest in music led
them to manufacture high fidelity components
of uncompromising quality founded Rotel over
40 years ago. Over the years that passion
has remained undiminished and the goal of
providing exceptional value for audiophiles
and music lovers regardless of their budget,
is shared by all Rotel employees.
The engineers work as a close team, listening to, and fine tuning each new product
until it reaches their exacting musical standards. They are free to choose components
from around the world in order to make that
product the best they can. You are likely to
find capacitors from the United Kingdom and
Germany, semiconductors from Japan or the
United States, and toroidal power transformers
manufactured in Rotel’s own factory.
Rotel’s reputation for excellence has been
earned through hundreds of good reviews
and awards from the most respected reviewers in the industry, who listen to music every
day. Their comments keep the company true
to its goal – the pursuit of equipment that is
musical, reliable and affordable.
All of us at Rotel thank you for buying this
product and hope it will bring you many
hours of enjoyment.
Getting Started
Thank you for purchasing the Rotel RKB-2100
Stereo Power Amplifier. When used in a highquality music or home theater system, your
Rotel amplifier will provide years of musical
enjoyment.
The RKB-2100 is a sophisticated two-channel
power amplifier. Discrete output devices, a
massive power supply with toroidal transformer, premium components, and Rotel’s
Balanced Design ensure superb sound quality.
High current capability allows the RKB-2100
to drive difficult speaker loads with ease.
Features
• Two-channel power amplifier, with 100
watts per channel output into 8 ohms.
• Rack-mountable (standard international
3U rack height). Rack handles or the rack
mount kit can be removed for installation
in narrower spaces.
• Front panel input level controls. Can be
configured three ways: recessed adjustments, knobs for user control, or covered
with blanking plugs to prevent user adjustment.
• User-selectable power on/off configuration: manual, automatic signal sensing,
or controlled by remote 12 volt trigger
signal.
• Provision for installation of optional cooling fan for increased heat dissipation and
performance.
• Protection circuitry against fault conditions
with front panel indicator.
A Few Precautions
Please read this manual carefully. In addition
to basic installation and operating instructions, it provides valuable information on
various RKB-2100 system configurations as
well as general information that will help you
get optimum performance from your system.
Please contact your authorized Rotel dealer
for answers to any questions you might have.
In addition, all of us at Rotel welcome your
questions and comments.
Save the RKB-2100 shipping carton and all
enclosed packing material for future use. Shipping or moving the RKB-2100 in anything other
than the original packing material may result
in severe damage to your amplifier.
Keep the original sales receipt. It is your
best record of the date of purchase, which
you will need in the event warranty service
is ever required.
Placement
The amplifier can be mounted in a standard equipment rack or placed on a solid
surface.
When not using an equipment rack, place
the RKB-2100 on a solid, level surface away
from sunlight, heat, moisture, or vibration.
Don’t stack other components or objects on
top of the RKB-2100. Don’t let any liquid fall
into the unit.
Likewise, remember the weight of the amplifier when you select an installation location.
Make sure that the shelf or cabinet can support its considerable bulk.
The RKB-2100 generates heat during normal
operation. Do not block ventilation openings. Allow a minimum of 10 cm or 4
inches of unobstructed space around
the unit. If installed in a cabinet, make sure
that there is adequate ventilation.
Rack Mounting
The RKB-2100 is supplied with two rack mounting brackets for installation in standard equipment racks. To install these brackets:
1. Hold a bracket against the side of the amplifier to locate the chassis cover screw
that must be removed for clearance. Remove this screw with a Phillips head screw
driver and replace it with one of the short
Philips head machine screws enclosed
with the brackets.
2. Install the rack mount bracket, inserting three
of the long Philips head machine screws
through the bracket and into the threaded
holes in the side of the amplifier.
3. Repeat for the bracket on the other side
of the amplifier.
RKB-2100 Power Amplifier
NOTE: You can remove the feet from the bottom of the amplifier if necessary for clearance
in the rack. Save the feet and hardware for
future use.
After the adaptors are installed, use four bolts
supplied with your equipment rack to mount
the amplifier. Be sure that all four bolts are
tightened properly.
Rack Handles
The rack mount brackets are supplied with
handles which can be installed or removed.
The handles are installed with two of the
long Philips head machine screws inserted
through the rack mount bracket and into the
threaded holes in the handle. If you do remove the handles, use the rubber hole plugs
supplied with the bracket hardware to fill the
exposed holes.
8
AC Power and Control
AC Power Input
Your RKB-2100 is configured at the factory
for the proper AC line voltage in the country
where you purchased it (USA: 120 volts/60
Hz, Europe: 230 volts/50 Hz). The AC line
configuration is noted on a label on the
back panel.
The RKB-2100 is supplied with the proper AC
power cord. Use only this cord or an exact
equivalent. Do not modify the supplied cord.
Do not use an extension cord.
Be sure the power switch on the front panel
of the RKB-2100 is turned off. Then, plug one
end of the cord into the AC power connector
on the back panel of the amplifier. Plug the
other end into an appropriate AC outlet.
If you are going to be away from home for
an extended period of time, it is a sensible
precaution to unplug your amplifier.
Power Switch
Indicator LED
The power switch is located on the left side
of the front panel. To turn the amplifier on (or
to activate either of the optional automatic
power-on modes), push the switch in. The
LED indicator above the switch will light,
indicating that the amplifier is turned on. To
turn the amplifier off, push the button again
and return it to the out position.
Optional Fan Kit
The RKB-2100’s generous heatsinks provide
adequate cooling for most installations. However, when rack mounting or otherwise installing the amplifier in a confined space near
other heat-generating components, additional
cooling may be desirable. The optional RKBF1 fan kit can be easily installed for additional
forced air cooling. In addition to lowering
operating temperatures, the optional fan kit
improves the performance of the amplifier,
especially when driving difficult loudspeaker
loads. See your Rotel dealer for information
on the optional fan kit.
NOTE:
The optional cooling kit generates mechanical fan noise during operation. When
using the fan cooling, select a location for
the amplifier where the noise will not be
intrusive.
Auto Turn On/Off Mode
Selector
The RKB-2100 provides three different options for manual or automatic power on/off
operation. These modes are selectable using a three-position slide switch on the back
panel as follows:
• With the switch in the OFF position,
the amplifier is turned on or off manually
using the front panel power switch. Also
use this mode if you are using a switched
AC outlet to control power to the amplifier.
• With the switch in the SIGNAL
SENSE position, the amplifier turns on
automatically when a signal is detected
at the inputs. The amplifier will go into
standby mode several minutes after no
signal is no longer present. The front
panel power switch overrides this function.
It must be ON for the signal sensing to
work. Turning the switch OFF cuts power
to the amplifier, regardless of whether or
not a signal is present.
• With the switch in the 12V TRIG
position, the amplifier is turned on automatically when a 12 volt trigger signal is
present at the 12V TRIG input to the left of
the switch. The amplifier goes into standby
mode if the +12 volt signal is not present.
The front panel POWER SWITCH overrides this function. It must be ON for the
+12V trigger to work. Turning the switch
OFF cuts power to the amplifier, regardless of whether or not a trigger signal is
present.
12V Trigger Input
An input jack for connecting the wires carrying a +12 volt trigger signal from a Rotel
preamp or surround sound processor to turn
the amplifier on and off. To use this feature
the adjacent slide switch must be placed to
the left position (see previous section).
The TRIGGER INPUT accepts any control signal
(AC or DC) ranging from 3 volts to 30 volts.
Using a cable with mono 3.5 mm mini-plugs
on both ends. The +12 V DC signal appears
at the “tip” connector.
12V Trigger Output
The 12V TRIG jack labeled OUT is used to
pass the remote turn-on signal to a second
Rotel amplifier. Any 12V Trigger signal at
the INPUT jack will be passed through to
the OUT jack.
Circuit Breaker
A 16 amp circuit breaker on the rear panel
protects the amplifier’s electrical circuity.
Generally, the circuit breaker will only open
under a fault condition which results in excessive current draw. To reset the circuit breaker,
press the button. Should it repeatedly open,
contact your authorized Rotel dealer for
troubleshooting assistance.
Protection Indicator
A thermal protection circuit protects the amplifier against potential damage in the event of
extreme or faulty operating conditions. Unlike
many designs, the RKB-2100’s protection circuit is independent of the audio signal and has
English
9
no impact on sonic performance. Instead, the
protection circuit monitors the temperature of
the output devices and shuts down the amplifier if temperatures exceed safe limits.
In addition, the RKB-2100 includes overcurrent protection which operates only when
load impedance drops too low.
Should a faulty condition arise, the amplifier
will stop playing and the PROTECTION LED
on the front panel will light.
If this happens, turn the amplifier off, let it
cool down for several minutes, and attempt
to identify and correct the problem. When
you turn the amplifier back on, the protection circuit will automatically reset and the
PROTECTION LED should go out.
In most cases, the protection circuitry activates
because of a fault condition such as shorted
speaker wires, or inadequate ventilation
leading to an overheating condition. In very
rare cases, highly reactive or extremely low
impedance speaker loads could cause the
protection circuit to engage.
Input Level Controls
Two controls on the front panel, one for each
channel, provide input level adjustments. These
allow you to adjust the gain of the amplifier
to match other components in the system.
The L level control changes the gain of the
left channel; the R level control changes the
right channel.
To adjust these controls, use a small, flatblade screwdriver. Turn the control clockwise
to increase gain. Turn counterclockwise to
reduce gain.
For easier adjustment, install the supplied volume control knobs by gently pressing them
onto the control shafts. Alternatively, you can
prevent inadvertant adjustment by installing
the supplied rubber plugs to conceal the volume controls.
Signal Connections
The RKB-2100 provides standard conventional
input connections — unbalanced RCA type
connections as found on nearly all audio
equipment. In addition, there is a pair of
SIGNAL OUTPUT LINK connections for passing the unchanged input signal on to another
audio component.
See Figure 2
Connect the left channel output of your preamp to the LEFT INPUT on the RKB-2100.
Connect the right channel of your preamp
to the RIGHT INPUT.
The RKB-2100 has two pair of speaker connectors, one pair for each channel.
Speaker Selection
The nominal impedance of the loudspeaker(s)
connected to the RKB-2100 should be a
minimum of 4 ohms. When driving multiple
pairs of speakers connected in parallel, the
effective impedance the amplifier sees is cut
in half. For example, when driving two pair
of 8 ohm speakers, the amplifier sees a 4
ohm load. When driving multiple speakers
in parallel, select speakers with a nominal
impedance of 8 ohms or higher.
Speaker Wire Selection
Use insulated two-conductor stranded wire
to connect the RKB-2100 to the speakers.
The size and quality of the wire can have
an audible effect on the performance of the
system. Standard speaker wire will work,
but can result in lower output or diminished
bass response, particularly over longer distances. In general, heavier wire will improve
the sound. For best performance, you may
want to consider special high-quality speaker cables. Your authorized Rotel dealer can
help in the selection of appropriate cables
for your system.
Polarity and Phasing
RCA Inputs
These RCA inputs accept audio signals from
preamplifiers or surround sound processors.
Use high quality audio interconnect cables
for best performance.
Speakers
Signal Output Link
This pair of RCA connections can be used to
pass the unprocessed input signals to another
audio component, for example to “daisychain” an additional amplifier to drive a
second set of speakers. Any INPUT SIGNAL
is also available at these LINK outputs.
The polarity or positive/negative orientation
of the connections for every speaker and amplifier connection must be consistent so all the
speakers will be in phase. If the polarity of
one connection is mistakenly reversed, bass
output will be very weak and stereo imaging
degraded. All speaker wire is marked so you
can identify the two conductors. There may be
ribs or a stripe on the insulation of one conductor. The wire may have clear insulation with
different color conductors (copper and silver).
There may be polarity indications printed on
the insulation. Identify the positive and negative conductors and be consistent with every
speaker and amplifier connection.
RKB-2100 Power Amplifier
Speaker Connections
See Figure 2
The RKB-2100 has one pair of color coded
connections per channel. Labels above the
connectors show the proper connections.
These speaker connectors accept bare wire,
connector lugs, or “banana” type connectors
(except in the European Community countries
where their use is not permitted).
Route the wires from the RKB-2100 to the
speakers. Give yourself enough slack so you
can move the components enough to allow
access to the speaker connectors.
If you are using banana plugs, connect them
to the wires and then plug into the backs of
the speaker connectors. The collars of the
speaker connectors should be screwed in all
the way (clockwise).
If you are using terminal lugs, connect them
to the wires. If you are attaching bare wires
directly to the speaker connectors, separate the
wire conductors and strip back the insulation
from the end of each conductor. Be careful
not to cut into the wire strands. Unscrew (turn
counterclockwise) the speaker connector collar. Place the connector lug around the shaft,
or insert the bundled wire into the hole in the
shaft. Turn the collars clockwise to clamp the
connector lug or wire firmly in place.
NOTE: Be sure there are no loose wire strands
that could touch adjacent wires or connectors.
Connect the left speaker to the pair of speaker
connectors labeled LEFT. Connect the right
speaker to the speaker connectors labeled
RIGHT. Follow the labels printed above the
connectors, Make sure that the positive terminal of the speaker is connected to the +
terminal on the amplifier. Make sure that the
negative terminal of the speaker is connected
to the – terminal of the amplifier.
10
Troubleshooting
Most difficulties in audio systems are the result
of poor or wrong connections, or improper
control settings. If you encounter problems,
isolate the area of the difficulty, check the
control settings, determine the cause of the
fault and make the necessary changes. If you
are unable to get sound from the RKB-2100,
refer to the suggestions for the following
conditions:
Front Panel Power Indicator Is
Not Lit
No main power to the RKB-2100. Check AC
power connections at the amplifier and the AC
outlet. Check the front panel power switch.
Make sure that it is set to the ON position.
If using signal sensing auto power-on, make
sure that a signal is present at the inputs. If
using 12V trigger power-on, make sure that
a trigger signal is present at rear panel +12V
TRIGGER connector.
No Sound
If the amp is getting AC power, but is producing no sound, check the PROTECTION
INDICATOR on the front panel. If lit, see below. If not, check all of your connections and
control settings on associated components.
Make sure that your input connections and
speaker connections match your selected
stereo/mono configuration.
Protection Indicator Is Lit
The front panel PROTECTION INDICATOR
lights when the RKB-2100 protection circuits
have shut off the amplifier. Typically, this occurs only when the ventilation openings are
blocked, when there is faulty speaker wiring,
or after a period of extreme use. Turn off the
system and wait for the amp to cool. Then
push the front panel power switch in and out
to reset the protection devices. If the problem
is not corrected or reoccurs, there is a problem
with the system or the amplifier itself.
Specifications
Continuous Power Output into 8 ohms
(20-20k Hz, < 0.03% THD)
100 watts/ch into 8 ohms, all channels driven
Continuous Power Output into 4 ohms
(DIN 1 kHz,1.0% THD)
170 watts/ch into 4 ohms, all channels driven
Total Harmonic Distortion
(20Hz-20kHz, 8 ohms)
Continuous rated power: < 0.03%
One-half rated power: < 0.03%
1 watt power: < 0.03%
Intermodulation Distortion
(60 Hz : 7 kHz, 4:1)
< 0.03%
Damping Factor
(20-20,000 Hz, 8 ohms)
>200
Input Impedance
20 k Ohms
Input Sensitivity
1.0 volt
Amplifier Gain:
29 dB
Input Overload Level
5.0 volt
Peak Current
> 60 A
Frequency Response (±1 dB)
4Hz-100kHz
S/N Ratio (IHF A)
120 dB
Crosstalk/Separation
> 70 dB
Speaker Impedance
4 ohms minimum
Auto Turn On Level (with all inputs)
3 mV input signal
Power Requirements
USA: 120 Volts, 60 Hz
Europe: 230 Volts, 50 Hz
Power Consumption
450 Watts
Idle: 40 Watts
Standby: 2.3 Watts
Dimensions (W x H x D)
(not including rack adaptors)
430 x 144 x 328 mm
16.9 x 5.7 x 12.9 in
Weight (net)
11.2 kg, 25 lb.
Panel Height
3U, 132.6 mm/5.2 in
When sizing openings in custom cabinets, measure the unit to be installed and/or allow at least
1 mm clearance on all sides for unit to unit tolerances.
All specifications are accurate at the time of printing. Rotel reserves the right to make improvements without notice.
Rotel and the Rotel HiFi logo are registered trademarks of The Rotel Co, Ltd., Tokyo, Japan.
The Rotel Co. Ltd.
10-10 Shinsen-Cho
Shibuya-Ku
Tokyo 150-0045
Japan
Phone: +81 3-5458-5325
Fax: +81 3-5458-5310
Rotel of America
54 Concord Street
North Reading, MA 01864-2699
USA
Phone: +1 978-664-3820
Fax: +1 978-664-4109
Rotel Europe
Dale Road
Worthing, West Sussex BN11 2BH
England
Phone: +44 (0)1903 221600
Fax: +44 (0)1903 221525
Rotel Deutschland
Kleine Heide 12
D-33790 Halle/Westf.
Germany
Phone: +49 05201-87170
Fax: +49 05201-73370
www.rotel.com
082 OM-RKB-2100 022105
English