Inter-M R500 Plus possible bias problem

Hello fellow forum members,

I've purchased this amplifier in used condition for mid-bass duty in a bi-amp setup. The problem is when idling it gets too hot. Can you help me set the correct bias voltage? I see two test points on the main board TP1 and TP2. Below I attach a photo of the amp. You can see the heat damage on the pcbs. Any help greatly appreciated.


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Also on the silk-screening is "IDLE", presumably on the other side is the bias trimmer.
Found the schematics/service manual:
Inter m r150 r300 r500 Power Amplifier Service Manual
TP1 and 2 are either end of two 0.47R emitter resistors.

As its an emitter-follower output stage try in the first instance for 50mV between testpoints TP1 and TP2, ie about 50mA per output pair.
So I measured the test points the channel 1 shows arround 20 mV and channel 2 30 mV

Well that's not unreasonable, it ought to be running cool. Can you measure the actual current consumption from the DC supplies?

Or the actual values of the emitter resistors - if they've changed in value that could be a reason. Also oscillation (ultrasonic or RF) might be another possible cause.
Thanks for the schematic but this is from the older model I have the plus model and I already have the service manual for that model. As for the bias I've set both channels at 30 mV. Now it runs a little colder on idle. If anyone knows the exact voltage it will be great.