Silver Supporting Member
Ok... I have a Fender Vibroverb that calls for all 5 filter caps under the pan to be 20mfd 525VDC. My tech has replaced the two closest to the OT with 100mfd 450VDC. WHY??? He says that's the value that came out of it. Well... it sounds like dogsh*t now and it sure didn't before and it's not what the schematic calls for. The other variable in this equation is the OT is now a Merc Mag Tone Clone of the original. The original failed years ago and all I could get at the time was a Ruby TF-125, which was supposed to be a generic replacement that worked in that amp fine. I gigged it for over two years with it in and it sounded decent, not as good as the original but decent. I decided I wanted it closer to the original though, so I ordered the Merc Mag tranny. The tech put it in and also changed those two filter caps he said were bad, but he said he used the same values that were there before. Now if the MM tranny and the Ruby were similar enough to work in that amp, wouldn't those caps 500% out of spec also have sounded like crap if they were there at that value before? Wouldn't a 100mfd cap in a position that calls for 20mfd smooth the ripple to the point that it would hardly load the power section?