Mini Rec probnlem: Thumping, pulsing noise when amps on.

[Adambomb]

Ok so I've had my Mini for about 1 1/2 years and it's worked great and still does.

There is a noise problem though and was wondering if anyone has had the same problem or could maybe help me figure out this pulsing thumping noise. It's not that loud but it's annoying. It's not the loop, I've tried several speaker cabs, cables, not pedals, and changed every preamp tube at a time. Only thing I haven't done is change the EL84 power tubes.

 

[Addictedtokaos]

Im thinking its your EL84s. It wouldnt hurt to have a spare set so that when they do start to go you can change them out.