Traynor YGM3 distorted reverb

[lowell]

Hi all,
I fixed the reverb in this amp. R26 was fried. I replaced it and it fried again. I replaced the driver tube and the coupling cap (C19) to the reverb tank. The reverb is quite full now. On another note it seems kind of distorted. Another problem is that when I put a new tube in the recovery/vibrato socket the vibrato makes a weird noise even when controls are turned down. Kind of a clicking/vibrato sound but just noise.

I don't believe that this is the correct tank either, maybe that's the problem. What might cause reverb distortion?

here's schem:
http://www.lynx.bc.ca/~jc/730911_YGM3_4.gif

[Rob Mercure]

Lowell,

While I used to be a minority on this board - but the crew changes - I like cap coupled reverb circuits and find that they give a better "gangle" and "whang" than the tranny coupled ones. But these have been either Ampeg amps or copies of Ampeg circuits that I've built. And the first difference I notice is that the Ampeg used high current capability/lower impedance tubes to drive the reverb - the Ampegs 6CG7s, which I mostly used but occasionally played with 12AU7s. So you might consider getting hold of an Ampeg schemo and copying some of their circuit - or at least trying a 12AT/U7 as the reverb driver and tweaking the values to meet. Oh, and the Ampeg are known for frying the same components that you mentioned with their more robust circuits.

As far as the recovery tube goes if the pot is turned all the way down you shouldn't hear anything. Maybe a thorough cleaning of all sockets, plugs, jacks, controls, etc. and checking grounds would be in order. Then consider using a more robust tube such as a 12AU7 and jacking up the drive signal if necessary - increasing the value of the 560 pf cap if necessary a bit.

Other than being a bit "underbuilt" this circuit should sound find. Oh, and as far as the reverb tank you can check the accutronics numbers - as best I remember this one should have around 2kOhms input.

Rob

[lowell]

Hey Rob,
Ok cool thanks! Good info. I will check on that 12au7... forget what it's all about... more current drive capability per the 12at7?