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The eco-friendly choice The Knoll GS8 and GS12 are class A/B amplifiers that produce 50
watts per channel at 8 ohms and 70 watts per channel at 4 ohms.
While offering unparalleled reliability, power and sound quality the
GS8 and GS12 offers a Knoll exclusive, the Eco-Drive-„˘ circuit. This
patent pending circuit determines wh ich of the 12 stereo channels (6
pairs) are in use and delivers power only to those channels needing it.
The channels that are off are truly off, not in standby or mute.
With this circuit the active channels share more rail voltage resulting
in more reserve power for the stereo channels in use. The most important feature of the Eco-Drive-„˘ circuit is the
electrical savings that is delivered to the owner over what a
comparable class A/B amplifier will cost to operate. The typical
homeowner will see a savings of a hund red dollars or more per year in
actual electrical costs and that ca n be multiplied when taking into
account the increased costs of air conditioning the home to extract
unwanted heat produced by a typica l multi-channel amplifier. The GS8
and GS12 also feature a very quiet energy saving thermostatically
controlled fan. A comparable amplifier without the Eco-Drive-„˘
circuit (we should know, we make lo ts of them) uses about 14 times
(65 watts) as much power while idling in standby. By comparison the
GS12 with Eco-Drive-„˘ uses under 5 watts while idling! For over 10 years Knoll multi-channe l amplifiers have sold around the
world because of their legendary reliability and unparalleled sound
quality. The GS8 and GS12 take the next logical step by being eco-
friendly. Please consider the envi ronment when choosing your next
system.
Sound cuts out 1. Verify spea ker impedance is 4-16 ohms.
Changing speakers may be required. 2. Check if the amp feels hot. If it's hot, increase cooling - see Installation. Sound is distorted 1. Turn the volume down. 2. Check speakers for damage. 3. Check inputs for proper levels. GS8 or GS12 ga in and source output level may have to be adjusted. 4. Speakers may be less than 4 ohms. GS8 or GS12 does not 1. Turn GS8 or GS12 power switch off (out). turn off 2. With the power switch on, and all input channels music source turned on, very slowly adjust SENS on rear of amplifier in a clockwise direction until amp turns off. Speaker pops when 1. Speaker may need resistor placed amp turned on or off across terminal. Suggest 2k0 1/4 w. This discharges the speaker internal cap.
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8. Make sure the speakers in each room are connected in phase with
the amplifier + going to the speaker +. Out of phase speakers give
unstable imaging and poor bass response.
9. Connect the AC power into an outlet than can supply at least six
amps (750 watts) dedicated to each GS8 or GS12. 10. After the amp has been turned on adjust the SENS pot on the
rear of the amplifier if necessary. The SENS adjustment can be
adjusted up (clockwise) to make th e amp less susceptible to be turned
on due to nuisance noise and hum. If it is adjusted too high, the amp
may delay turn on or turn off duri ng a quiet music or speech passage. Caution: Never listen to sound that is distorted. If distorted sound is
heard, turn the volume down immedi ately or speaker and/or amplifier
damage could occur that is not co vered by the warranty. If this
problem persists, contact your dealer. User Adjustments and Service: There are no user adjustments
inside the GS8 or GS12. Your inst aller may make certain gain and
sensitivity level adjustment s on the rear panel. Caution: The GS8 or GS12 contains no user serviceable parts, so do
not attempt to open or repair the GS8 or GS12. Refer servicing to a qualified techni cian only or contact the factory
for information. Troubleshooting If a problem is encountered with the GS8 or GS12 amplifier, the
most expedient procedure is to locate the problem and if possible
repair it before requesting service. Be sure to carefully check other
system components such as controlle rs, CD players, volume controls,
wiring, speakers, etc. that may be at fault. Problem Action Power led does 1. Check that the GS8 or GS12 is plugged in. not light - no sound 2. Test the AC outlet with a lamp. 3. Check GS8 or GS12 power button on (in). 4. Slowly turn down the SENS adjustment (counterclockwise) on the amplifier rear, until the amplifier just turns on.
Installation Installing the amplifier should be relatively easy. With a bit of
planning, this amplifier will give trouble free service for years. 1. The most important considerat ion when installing the GS8
and/or GS12 is cooling. This amplifier has a lot of power packed into
a small chassis size. When installing it in an equipment stack, it should
be the top component. It needs at least 3"-5" of space above the
amplifier to allow for adequa te convection cooling. 2. When installing the GS8 and/or GS 12 in a rack we suggest adding
a 3-1/2" blank above and below the amplifier. In multiple GS8 and
GS12 installations, plan for a 3- 1/2" blank (double) between each
amplifier and a 3-1/2" blank on the top and bottom. Amplifiers should
always be the top components in a rack system. 3. The GS8 and GS12 are available as an optional 19" EIA rack mount
style. 4. Never operate a GS8 or GS12 on it s side, as the cooling potential
drops significantly when operated on the side. 5. Connect the GS8 or GS12 RCA inputs to the source component
outputs with good quality, short as possible RCA jack cables. Connect
each channel individually. 6. Connect the GS8 or GS12 speaker outputs to speakers using good
quality speaker wire. Minimum 16 gauge copper wire is recommended
with 14 gauge minimum for runs over 30' (10m). Fire-rated wire may
be required if installing wires in side walls, ceilings or floors. Note: Ideally the GS8 and GS12 amplifiers like 6-8 ohm loads.
Connecting to 4-ohm loads won't hurt the amplifier, but the channels
connected to 4-ohm loads may o ccasionally shutdown due to
overloading. Never connect any GS8 or GS12 amplifier to less than 4
ohms. 7. Individually adjust the channel gain s as required. Ideally, all gains
are fully on (fully clockwise).
