citronic ppx help and rotel question

[lt cdr data]

I ahve a ppx that's distorting, can't find anything wrong apart from 1 power mosftet that appears to have gone, wouldn't the rest work in push pull tho still and it would't really matter?

its pretty standard hitiach mosfet schematic, 2 diff pairs and that old, its mostly passively current sourced.

And I heard stan ? talk about a rotel amp, he designed, 820? saying there was a power supply "trick" to make bass drums better? any ideas what it was?

simple as a diode in the power supply line, tho can't understand why that rectifies the psu, as you still get i squared r losses in the transformer windings....a reg. power supply only keeps the power from rising, not falling, it can't make something out of nothing....

[Xoc1]

I have a ppx that's distorting, can't find anything wrong apart from 1 power mosftet that appears to have gone

If one mosfet has obviously failed then I would physically remove that component. The gate may have shorted and that could be causing the distortion. When the amplifier is switched on, with no signal, there should be no measurable voltage across the gate resistors. Any voltage across the 1k gate resistors indicates that that mosfets gate is damaged.