SVT-VR splattery distortion

[Prairie Dawg]

Folks, I've got an SVT-VR on the bench here that's kicking my butt up and down the street.

It's about four month old B stock so no warranty which is why it's here. I should add that it looks like it was put together with old parts because the boards are all dated 2007. I't's got a splattery distortion in both channels when you strike a fairly vigorous note, and I can get it to do it with my Tele which is what I'm testing it with.

To date I have: subbed all the tubes with known good ones cleaned the sockets, resoldered all the connections on the preamp board, switch boards, driver board and tube board. In addition I've tested all the usual suspect high wattage resistors. on the driver board and checked everything I could for opens and shorts.

I'm getting pretty good at ripping it apart and putting it back together but that's about all.

I've still got the problem. What am I not seeing? Helpful hints? Ideas?

Thanks in advance.

 

[bassmanbiff]

sounds like a job for an oscilloscope and a walk though the signal path

 

[BassmanPaul]

Feed a lowish frequency into the beast, turn up until the problem happens and trace the signal path with a scope.

Paul

 

[Jerrold Tiers]

sounds like a job for an oscilloscope and a walk though the signal path

Absolutely.

NO otehr way you are gonna find that in a reasonable time. It will pinpoint the problem area, and tehn you can measure voltages etc and get a real diagnosis.

You know this , we are just reinforcing it for you because it is easy to forget the methodical slog when you have tried a couple of the quick-fixes that usually work.