Audio Research Reference 75 SE, Руководство пользователя

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14
Operation
Output Tube Bias Adjustment
As shipped from the factory, the output
‘bias’ adjustments are set for a nominal
65mA per KT150 tube. Under these idle
conditions the tubes are each dissipating
approximately 27 watts of their 60
watt rating. This point of operation
provides ‘enriched’ Class AB1, and will
satisfy the most critical listener.
For best results, operate and adjust
the Reference 75 at 117.5 VAC (230
VAC). Adjustment must be made
under zero-signal conditions
after at least 15-20 minutes of
uninterrupted stabilization time.
With the amplifier warmed up and signal
set to zero, switch the rotary knob to
one of the ‘V’ settings. Insert only the
supplied non-conductive bias adjustment
tool into the appropriate bias adjustment
holes. Slowly turn the bias adjustment
potentiometer in each of the holes
marked with the output tube ‘V’ number
position only when the bias switch is set
to that associated ‘V’ number position.
The meter should be set to read in the
center of the tube bias arc (@65mA)
for each of the four output tubes V1 –
V4 for optimum sonic performance.