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SF Twin with low ditorted volume

8/27/2004 10:18 PM
Dustie	SF Twin with low ditorted volume I just did a cap job on a silverface twin reverb for a bandmate.They were the original caps. I also cleaned and lubed all the pots,cleaned and retentioned all the tube sockets,put new output coupling caps in,replaced all the 25@25 on board caps and the bias cap.The amp has new JJ/tesla tubes. Before I worked on the amp it had low distorted volume.The volume is better now but still low and distorted.There is 465V on the output tube plates but the bias is odd.I tried measuring it with a Weber bias meter and I'm getting like 5ma.All the resistors in the bias circuit check out and I've changed the caps.I've also checked all the solder joints and grounds and they seem to be fine.Can anyone tell me what is going on with the bias ? Any help is appreciated.

8/27/2004 10:18 PM

Dustie

SF Twin with low ditorted volume

I just did a cap job on a silverface twin reverb for a bandmate.They were the original caps.
I also cleaned and lubed all the pots,cleaned and retentioned all the tube sockets,put new output coupling caps in,replaced all the 25@25 on board caps and the bias cap.The amp has new JJ/tesla tubes.
Before I worked on the amp it had low distorted volume.The volume is better now but still low and distorted.There is 465V on the output tube plates
but the bias is odd.I tried measuring it with a Weber bias meter and I'm getting like 5ma.All the resistors in the bias circuit check out and I've changed the caps.I've also checked all the solder joints and grounds and they seem to be fine.Can anyone tell me what is going on with the bias ?
Any help is appreciated.

Replies:

Enzo It always pays to solve the problem... -- 8/27/2004 11:50 PM
Enzo Thanks for the kind words. That is... -- 8/30/2004 11:23 PM