Traynor YVC80 Low Bass Level - Control Not Working

[TomCarlos]

Gents...

Last year, I opened a thread to help me rebuild a Traynor VYC80. The amp is working BUT... there is hardly a low end. I tested the speakers with another amp and they can produce some bass. So there is something going on with the amp.

I tested the amp and the output is ok- pushing around 50 - 55 watts before clipping. I can adjust the Treble and Mid controls and see the output changing. But the Bass adjust hardly does anything. Since these pots are inline, it probably isn't a tube? I guess I'll start pulling parts after V2:B and before the Volume pot to test and see if they are in spec.

Any other ideas?

Thanks,

Tom

[Leo_Gnardo]

Larger cathode bypass caps should help. Clean channel 1st stage is a skinny 1 uF, bump that up to 3 or 5 or so.

On the OD side, I'd increase the cathode bp on the 2nd stage similarly. Leave the 1st stage alone, it's best to keep a "thin" tone when it's going to be boosted in an OD situation or the tone gets muddy. You can clip in caps to evaluate what they'll do before you commit to soldering.

[TomCarlos]

Thanks Leo.... I will take a look at that.

I really don't care for the Overdrive Channel. I would like the clean channel to sound "full." Right now, it's thin.

Tom

[52 Bill]

The thing that I noticed was the value of the three tone pot, they are very different in value from the usual Blackface Fender values. Somewhere online there is a tone stack calculator that you could use to find out what frequencies the controls work at and see if changing a pot will get you to a better sound. Or it may mean that you will need to change a few of the tone stack caps.

[TomCarlos]

Hi Bill....

Funny you should say that because I too was looking at a Fender Twin circuit and a couple others. I am going to experiment a bit now that I have the circuit boards pulled out of the chassis.

Thanks!