#1
This is not your normal feedback. This is a 1 pitch ear destroying squeal! It happens when I kick in a distortion pedal or od on the amp at high volume. I can crank the clean channel to whatever I want, but if I have the ds1 set to a vol that I need. Instant squeal! Has anyone experienced this? Be it with a hotrod deville or deluxe? I played my first shows ever and had to use a vox ac30 from another band(mic'd), which sounded awesome..and borrow a deluxe limited edition with vintage 30. That was unmic'd and definitely could have used more juice! I was getting some feedback from that as well, but more feedback and not squeal. Ive heard of bad soldering in these amps. Took it to a shop, and they just seemed to thing I was over driving the amp, which I think is BS, as this just started happening. I can disconnect my pedal board and just use the footswitch, and get it to squeal on the I'd channel. I've switched out a bunch of preamp tubes, but not the power tubes...it's really pissing me off. I'm thinking about gutting the deville, and using it as a cab, and get a silverface bassman head or something that takes pedals well.

Thanks
#2
Could be a microphonic pickup, tried different guitars to see if you still have the same problem?
#3
Quote by Lordshanks
Could be a microphonic pickup, tried different guitars to see if you still have the same problem?


I do believe I might have a microphonic pickup in my Tele Deluxe. My buddy packed in some foam on the neck pickup and seemed to go from the neck to the bridge pickup now. But, I am still getting a squeal from my Strat and buddies SG...

I get a big thump if I tap V1 tube....And If I crank it on the OD channel with no guitar connected and thump the V1, I can get it to thump then squeal. I've tried a bunch of tubes, but get the same thump no matter the tube. Maybe a bad socket?
#4
that tube is probably microphonic. V1. when u tap, it becomes a thump. so if you have loud notes blasting on the tube, that note being blasted becomes a small vibration, and small vibration becomes even bigger from the amplification.
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#5
Quote by ECistheBest
that tube is probably microphonic. V1. when u tap, it becomes a thump. so if you have loud notes blasting on the tube, that note being blasted becomes a small vibration, and small vibration becomes even bigger from the amplification.



Since I've tried about 5 different tubes in V1 and they all THUMP, is it more then likely a socket or wiring etc?
#6
Thump is common and expected for an healthy input stage valve. Microphonic valves will squeal or otherwise emit a nasty sound when you tap on them.

On one hand, it seems as though the amp is oscillating at high volumes due to the increase in gain. This could be something as simple as a bad preamp valve, or something as dooming as just a plain poorly designed preamp section. I've yet to hear anyone speak highly of the drive channel on the Hotrod Series, so this is possible.

You swapped out V1 for numerous other preamp valves, but did you swap out any of the others? Did you at least try thumping on the other valves?

There also exists the possibility that a solder joint on the socket pins is bad, although I would doubt it if the clean channel functions properly. But let's not get ahead of ourselves just yet. We need to rule out the valves.
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Last edited by ConfederateAxe at Apr 18, 2011,
#7
Yep, I've tapped all the tubes, only v1 thumps. The amp is disturbed by gain. I always run clean channel with pedals. As soon as I click a ds1, ts808, big muff etc it just goes into squealing orbit. A local shop seemed to believe I was over driving it, but it only recently started happening.