Genelec S30 repair part 1

I trying repair Genelec s30's.
- its a three way active speaker

- bass, mid, treble has its own amp

- treble unit was short circuited, burning transistors

- no short circuit in the cable or ribbon tweeter

- changed many parts and got it running except bias reads ZERO!

- dc offset is within limits and reacts to trimmer

- bias is 0.00v and doesnt react to the trimmer

- bias trimmer pot is tested and ok, resistors attached to bias circuit are ok, capasitor in bias circuit was changed

- transistors were changed and tested too (with cheap component tester)

- attachment has the schematic and some info

Why bias stays zero and where is the fault?


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