lanzar optidrive 2500 abortion

These boards are very easily damaged. Be careful when pulling the old parts.

I have information on a 50C and it should be essentially the same as your amp. The circuit board designations are for the 50C. You'll have to confirm that they're the same in your amp.

These notes are from an amp that had been repaired before. I think the original transistors were 2N4401/4403 (NPN/PNP).

FET drivers for one bank of FETs
Q63 - PNP
Q64 - NPN

FET drivers for other bank of FETs
Q61 - PNP
Q62 - NPN

If yours has different designations, you can determine which ones to use by checking continuity. The collectors of the PNP transistors of the emitter follower pairs go to ground. The base and emitter of the NPN/PNP transistors of the follower pairs are directly connected.

Protection Circuit
Q86 - PNP

I'm not sure about the unreadable transistor. The only remaining semis in that area are a regulator (U9 - TL431) and a PNP transistor (Q60 in this amp)..

The FETs in the amp I repaired were IRFZ40s. IRFZ44s would be a good replacement.