Maintenance Information - Cello PERFORMANCE AMPLIFIER II Owner's Manual

Instructions (cont.)
your Cello Designer. The bridging kit
comes with the proper quantity of parts to
convert two sets of Performance Amplifi-
ers (four supplies, four amps)to stereo
operation by combining one set of amps
for the left channel and one set of amps
for the right channel.
The following instructions are for
connecting only one set of amps (one
channel). To connect for stereo, simply
repeat the procedure on the second set of
amps. See the block wiring diagram for
bridged operation to identify these
connections.
1) Connect all AC and DC cables as
instructed previously.
2) Make all input connections to one
amplifier only.
3) Connect the input jumper cable from
the bridging output connector of the
first amplifier into the input connector
of the second amplifier.
4) Connect the speaker high lead to one
of the output terminals labeled "H"
(high) on the first amplifier. Connect
the speaker low lead to one of the
output terminals labeled "H" (high) on
the second amplifier.
5) Connect the output ground jumper
cable from one of the output terminals
labeled "L" (low) on the first amplifier
to one of the output terminals labeled
"L" (low) on the second amplifier.
6) Connect the DC bridging cable, using
the color code, from the supply
terminals on the first amp to the
supply terminals on the second amp.
After repeating the above procedure
on the second set of amps the amplifiers
are ready for use in stereo. CAUTION:
Make certain the preamp volume is turned
down to minimum. Turn AC power "on"
for operation.

MAINTENANCE INFORMATION

The Performance Amplifier is essentially a
maintenance-free device designed to last
for many decades of enjoyment. No
routine maintenance or adjustments are
required, however it is recommended that
you undertake two actions.
1. Periodic cleaning of the foam fan-air
filters.
When these filters become clogged
with dirt and dust, the ability of the
PERFORMANCE AMPLIFIER
amplifier to dissipate heat is reduced. To
clean them, gently pull the plastic grille
covers off. Rinse foam filters in cold
water, allow to air dry, then re- install.
2. Care of finish.
The finish of the Performance Ampli-
fier is of brushed and anodized alumi-
num. Ammonia based glass cleaner or
alcohol works well to restore the shine
and remove fingerprints. Be sure that
the units are off and unplugged before
cleaning and that excess cleaning fluid
does not get inside the amplifier. Take
care when cleaning near printed words
not to rub so hard as to remove the
printing.
WIRING FOR DIFFERENT
LINE VOLTAGES
For voltage change information,
contact the factory.
240V OPERATION
Some 220V lines run high, in some
cases close to 240V. This may cause
mechanical noise in the supply chassis if it
is set for 220V. Changing to 240V
operation may solve this problem.
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