Tube amp with Tremolo

[Krohawk2]

I don't play too much electric, but I've started to play them a little more lately. I've got a Vox AC15 (approx. 10yrs old) and an old Gibson Discovery amp, both with tremolo. When I first got both the amps, they both worked normally, but now when I turn the tremolo effect on, (in both amps) I get a "warbling" sound when I'm not playing. The tremolo sound fine when I play, and the amps sound fine when the tremolo is not engaged, but when it is engaged I get that noise. Some people tell me "that's normal", but I know that's not the case, as the amps never did that before. Not too many people in Buffalo, NY that I know that are knowledgeable about tube amps.

Any thoughts?

[mooonpi]

tube going?

[smurph1]

tube going?

Could be..try switching a couple tubes around and see if it goes away?

[DetroitBlues]

I'd suspect tubes as well. KBP810 just build me a RD amp with Tremolo. He might know.

[kbp810]

I'd suspect tubes as well. KBP810 just build me a RD amp with Tremolo. He might know.

Well... that's vibrato on the RD

 

I'd suspect the V3 Preamp tube - sounds like some noise or osciallation is making it's way through the signal chain when you are not playing, and it's getting colored by the trem circuit.

 

If some known good preamp tubes don't do the trick, then sorry to say she might need to have a lil' bit of surgery to see whats causing the noise.

 

Or if it's easier... just don't stop playing

[Krohawk2]

Well... that's vibrato on the RD

 

I'd suspect the V3 Preamp tube - sounds like some noise or osciallation is making it's way through the signal chain when you are not playing, and it's getting colored by the trem circuit.

 

If some known good preamp tubes don't do the trick, then sorry to say she might need to have a lil' bit of surgery to see whats causing the noise.

 

Or if it's easier... just don't stop playing

 

I sort of suspected tubes also, but like I said, I'm not electronically versed. You description nailed it. the noise oscillation being colored by the trem.

I'll check the tubes.

Thanks.