Trying to repair an older 4B ( silver rack handles) ?? not sure what version it is, but anyway it had a blown channel which I repaired with Onsemi outputs matched up. Testing reveals nice sine waves but not so much on square wave...
The left channel regardless of which heatsink module is bolted into the left side shows a square wave similar to one with added treble on the tone controls for lack of proper terminology lol. Figured I would ask over here for some wisdom on this amp. Fwiw I haven't really checked over the back input board yet other then a quick visual for any burnt looking components ,but that's my next plan.
