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8) Signal led channel 2: this led lights up green when a sufficiently strong signal is present
on the left channel, after passing the input level control. At startup, the led will light up red
during a few seconds, this is perfectly normal. When it lights up red during use, the power
transformer or power amplifier is overheated or in protect mode and is shut down. Turn off the
power.
The amplifier will not turn on automatically after most error conditions. In some
cases, the user MUST turn off power and remove the overload and then power on
again ! More details can be found in the table below.
9) 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.
10) Clip led channel 2: this led lights up whenever the amplifier clips. This is a warning sign: you
are pushing things a little too far or you are overloading the amp. Reduce the input level by a
few dB so that this led never lights up anymore ! Don’t ignore this !
11) Temp led left channel: this led lights up when the amplifier is about to overheat. Output power
will automatically be limited by the APC circuitry to avoid further overheating. This part of the
protection circuit resets itself automatically when temperature has normalized. When both
signal led (2) and temp led (5) are red, 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 ! More details can be found in the table below.
12) Volume potmeter channel 2: use this potmeter to preset the volume. In bridge mode, this
potmeter has no function.
