Pops

[c7sus]

Just retubed the Quiana, thought I had a preamp tube going microphonic.

I was getting this popping noise after the amp has been on a couple hours.

Replaced with GT12AX7-M's.

They sound great, break up a little sooner than I was hoping, but solid.

And then about 2 hours or so into playing last night I started getting the popping again.

Maybe it's a capacitor going bad. I don't know. Sounds almost like it's a 60-cycle pop. click-click-click-click. Really low volume, like a spitting sound.

I know somebody has had this issue before.

Please advise.

[killmachine]

Yup, it's a bad ground in the building... Those tubes amps are obviously more subseptable to it than SS amps. I have the same problems... You can try the ground lift switch if the amp as one but most of the time that pry won't do it. Sometimes if the amp gets to hot it'll get really noisy and actually start to loose power.

[c7sus]

it's not 60Hz hum. It's popping, and it occured to me this morning it's probably on the order of 60 times/sec.

I'm thinking it's a diode in the rectifier that is overheating and passing some voltage that it's not supposed to.

[Track Rat]

It sounds like a simular problem I had with my Pubster. It turned out to be a couple of smoked caps inside somewhere. It was still under warenty so I let them figure it out and fix it.

[David]

Originally Posted by c7sus

Just retubed the Quiana, thought I had a preamp tube going microphonic.

I was getting this popping noise after the amp has been on a couple hours.

Replaced with GT12AX7-M's.

They sound great, break up a little sooner than I was hoping, but solid.

And then about 2 hours or so into playing last night I started getting the popping again.

Maybe it's a capacitor going bad. I don't know. Sounds almost like it's a 60-cycle pop. click-click-click-click. Really low volume, like a spitting sound.

I know somebody has had this issue before.

Please advise.

I've had that same thing happen to my quiana Craig. It's always been a *ground* issue though. Have you tried plugging it in different places in your house? Hopefully that's what it is with yours.

Here's a link that might help ya along..(you may already know about it).
http://home.bellsouth.net/p/s/commun...pid=218298&ck=

Good luck.