ampeg svt 2 pro poping noise

[eulogy77]

hello there, i have an ampeg svt 2 pro, its been doing a poping noise, it does not affect the power nor sound, its not to loud but the louder i go on the power and or gain the louder it sounds, its not disturbing loud, it comes one once i switched from the stand by, in my guessing i think it might be a faulty cap, but no sure, if you any advice it would be very appreciated, one think i forgot to mention the driver tubes (12au7 x 2 and 12ax7 x 1) are unbalanced, could that be the problem, i just don want to spend any more money on getting robed by the techs (deltronics in Chicago) thanks

[Jerrold Tiers]

If the noise increases with the gain control it is probably in the very first stage of the unit.

Very possibly it is caused by the tube V1, which is the only tube that is before the gain control. In fact, only half of V1 is before the gain control.

I'd try swapping that tube with another 12AX7 before getting too excited about taking it to a tech.

[JimmyM]

how do driver tubes get unbalanced? is there something i've been missing? i thought they were just plug in and go.

[eulogy77]

thanks JT, i did what you suggested and the noise still there, i actually tried all the preamp tubes and driver tubes and nothing, im thinking it will be a cap, im not taking it to the tech anymore, ill try to change parts myself, i just need to get the capacitor tester, it is actually interesting to do all of this myself, the tubes where unbalanced when i bought them, dont know if this could be a problem,any more input will be greatly appreciated