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6) Signal led right channel, this led lights up green when a sufficiently strong signal is present on
the right channel, after passing the input level control. When it lights up red, the power amp is
overheated or in protect mode and is shut down. Turn off the power. The amplifier will not turn
on automatically after an error condition, the user MUST turn off power, wait for cooling down in
case of overtemperature, or remove the overload and then power on again !
7) APC activity led right channel: this led lights up when the APC circuitry is active. The APC
circuitry reduces the gain at the inputs to guarantee the full dynamic range of the power
amplifier circuits.
8) Clip led right channel: this led lights up whenever the ultrafast clip limiter becomes active. This
is a warning sign: you are pushing things a little too far: reduce the input level by a few dB so
that this led never lights up anymore ! Don’t ignore this !
9) Temp led right channel: this led lights up when the amplifier is about to overheat. Input gain
will automatically be reduced by the APC circuitry to avoid further overheating. This part of
the protection circuit resets itself automatically when temperature has normalized.
Caution:
turning off the APC circuit (rear switch ‘11’) will also turn off this protection feature and
will void warranty.
When both signal led (6) and temp led (9) are red, it is possible that the power transformer’s
thermal protection is active and the amplifier is shut down. Turn off the power and let it cool
down.
The amplifier will not turn on automatically after it has cooled down, the user
MUST turn off power, wait for cooling down and then power on again!
