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Power Switch:
Turns the amplifier on/off. This
switch does not disconnect the main power feed
from the amplifier; this requires that the power cord
be unplugged from the outlet.
Low Cut (High Pass) Switch:
Enables/disables the
filter that reduces very low frequency energy and
protects autoformer-based volume control/speaker
selectors. When “on,” the filter is set to -3dB at 40
Hz. When off, the frequency response is flat from
20Hz to 20kHz.
Gain Controls:
Left and Right gain controls inde-
pendently adjust the sound level for each channel.
When used in the bridged mode only the Left control
is used.
Loop Output:
The loop output is a passive
passthrough of the line input. These jacks can be
used to daisy chain the input signal to another
amplifier in the system.
Speaker A/B Outputs:
The A and B speaker out-
puts are in parallel to the amplifier output. The mini-
mum load in stereo mode is 4 ohms. This can be
used to drive up to 2 pairs of 8-ohm speakers or 1
pair of 4-ohm speakers. The minimum load imped-
ance for bridged mode operation is 8 ohms,
Speaker B only.
Stereo/Bridge Mono Switch:
Sets the pair of
amplifier channels for stereo or bridge mono opera-
tion.
Line Input:
The line audio input is a sensing input
that will activate the amplifier when an audio signal
from a source is present. When there is no audio
the zone will go into standby. The Left input is used
for bridged mono operation only.
AC Input:
The AC voltage input for the North
American model is 120VAC at 60Hz (for the
European model, 230VAC at 50Hz). This receptacle
accepts a 3-prong IEC 320 type connector. A
detachable 3-terminal power cord is included.
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R275HC AMPLIFIER
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