Tube Amp Archive

Yes, I replaced them before the 100k's. As far as I can tell I wasn't experiencing this noise.

Hey guys, So I replaced the plate resistors, and the noise has so far seemed to be remedied. Now, however, there is an intermittent "bonnnnggg" sound, for lack of a better term. It's a humming type noise that only last for a second. It usually happens when I take the amp off of standby, although it ...

Thanks guys, I'll let you know how it goes.

Great, thanks for the info. I'm not sure who serviced the amp last, but I aim to get it back within spec, and hopefully fix that awful crackling sound. I'll put in an order for a couple of new 70µF caps.

Is there any benefit to sticking with carbon comp?

Ya, it's tube rectified, and I've actually had to replace the rectifier already! I'll swap those two out as soon as I can.

If you have a chance to see my other post, I'm also experiencing an intermittent crackle/pop. Would that symptom have any relation to the overly large capacitor values?

The Spragues that were removed look great, and the other three in the power section are all Spragues, at 20µF I believe. My assumption is that the 220µ's were put in to provide some sort of advantage. Does this value seem too high? I couldn't find the specs on a schematic or layout, but a lot of peo...

Thanks for the quick responses folks, I'll order up a set a give them a shot.

Any thoughts about the arcing hypothesis? Maybe I could carefully lay some mesh wire on the chassis and watch for arcing.

Oh ok, so I forgot to mention that all of the capacitors look mechanically perfect. I have yet to test them, but it makes sense that he wouldn't have sent them to me if they were faulty parts. As for the large valued bypass cap, I read that something as high as 100µF when the stock value is 25µF wil...

Hello, I'm getting an intermittent loud crackling and popping sound from my 65' Pro Reverb (aa165). The noise is typically made worse by heavy strumming, but again, it is very intermittent and does not always come with heavy strumming. I've tried changing out the preamp tubes, cleaning the chassis c...

Hey, Thanks for taking the time. As the subject suggests, I have a few questions about my 65' Pro Reverb (aa165). When I bought the amp, it came with a much appreciated bag of replaced parts, particularly some capacitors. I don't have the ability to ask the former owner why these parts were swapped ...