Strange reverb issue with TA30 1x12 combo

[philh27]

Just picked one up recently and it is a truly wonderful amp. Not experiencing any noise issues with the loop/ reverb apart from one minor niggle that I haven't seen mentioned anywhere else. I wondered if anyone else had in fact had this problem and if they had managed to fix it.

Only on the Red (Tweed/ Hi1, Hi2) channel, but on all modes, all wattages, clean and overdriven,the reverb when cranked starts to emit a high pitched feedback type whistle. It starts low and slowly builds not to exceedingly loud proportions, but certainly noticeable. It feels like some kind of vibration induced 'feedback' but it does it at very low volume levels too. All the valves/ tubes have been tested and are fine. Seems odd that this only happens in the Red channel. No issues at all at any volume on the Green Vox channel.

I don't tend to use the amp reverb, so in practical terms it isn't really a problem for me, but I'd like to resolve if possible.

 

[bgh]

I tried the reverb on mine. On the red channel, no matter the mode or wattage on mine, I can crank the reverb ... and I get none of the feedback you describe. You might want to give Mesa a call and describe it to them. I have called them in the past and they have been extremely helpful in diagnosing things over the phone. It may be worth a shot.

 

[bgh]

One thing you may want to try is running a patch cable for your effects loop. In the TA-30, the effects loop must be engaged in order to use the reverb. I wonder if the issue may be in that part of the amp.

 

[philh27]

Thanks for your help. No the loop works fine- in fact though I don't tend to use effectsloops much nowadays, I'd say this one is possibly the best most transparent I've experienced.

It really is like a microphone just going over the next edge into feedback and only when the reverb is on full and only on that Red channel. Odd. It feels like it 'must' be tube related, but I have had them all tested. Perhaps I should replace them all?

I will contact Mesa first, though!

 

[Snottyboy]

@philh7 Did you resolve this issue with your TA-30?