Peavey 400 series amp board - Output xistors

[Mars Amp Repair]

Peavey had more than a few 400 series amplifiers.
Here are two that have the board layout.
Maybe one is close to the one that you have.

Thanx Jazz-P...but no attachment

[Helmholtz]

I see where the schemo indicates those drivers have 0.1V across their ballast resistors. That's about what they're measuring. Guess I don't see where those drivers would be running class A, but I'm not a designer and am open to any suggestions or ideas.

What I meant is that these drivers add a little class A power during crossover. At large signal they run in class AB.
But the outputs run in pure class B.

Not sure which of the schematics applies.

0.1V across 1R means 0.1A. With a supply voltage of 40V (?) that results in a dissipation of 4W at idle, while the outputs are essentially off (no dissipation).
The B-E voltages of the outputs should be identical to the drop across the 1R resistors.

[g1]

Thanx Jazz-P...but no attachment

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[g1]

I see where the schemo indicates those drivers have 0.1V across their ballast resistors.

I'm not saying that number is wrong, but I don't see it shown on the schematic anywhere?

[Enzo]

I see a .1v next to the emitter of the transistor, and I see a 0v at the output bus. Those points are also the ends of the 1 ohm resistor.

[g1]

I see a .1v next to the emitter of the transistor, and I see a 0v at the output bus. Those points are also the ends of the 1 ohm resistor.

I'm referring to the schematic Glen posted (post #4) and feeling somewhat the blind idiot right now.

[Enzo]

When I saw it was a 400 module, I opened a copy of my own so I could open it in a different reader.

[Mars Amp Repair]

Peavey had more than a few 400 series amplifiers.
Here are two that have the board layout.
Maybe one is close to the one that you have.

Thanx, Jazz-P. I think one of those power amp schemos matches what I have better. I'll puruse them & see what I can come up with...glen

[g1]

When I saw it was a 400 module, I opened a copy of my own so I could open it in a different reader.

Could you post that one? I don't think I have it.

[Enzo]

OK, see if this works

PV 400 module version A and B.pdf