7
1) Signal led left channel, this led lights up green when a sufficiently strong signal is present on
the left 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!
2) APC activity led left 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.
3) Clip led left channel: this led lights up whenever the amplifier clips. This is a warning sign: you
are pushing things a little too far or overloading the amp (minimum load impedance is 4 ohms
in 2 channel mode or 8 ohms in bridge mode). Reduce the input level by a few dB so that this
led never lights up anymore ! Don’t ignore this !
4) 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.
Caution:
turning off the APC circuit (rear switch ‘15’) will also turn off this protection feature and
will void warranty.
When both signal led (1) and temp led (4) 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 !
5) Power switch and power led: flip the switch to power on the amplifier. The led will light up to
indicate that mains power is present.
3. Inputs and outputs
Front panel layout:
1
2
3
4
6
7
8
9
5
