tube amp squeal...

astrozombie

KatyPerryologist
my hot rod deluxe squeals when I set it to "more drive" and set the gain at maximum. I also have super high output humbuckers.


is it just too much gain? the only time it squeals is when I set it to extremes.
 
Re: tube amp squeal...

Yeah pretty much. That's the main reason pickups are generally wax potted. It probably has more to do with the OD channel of the HRDx though as Its not really made for Uber Br000talzz Metulz.
 
Re: tube amp squeal...

Yeah pretty much. That's the main reason pickups are generally wax potted. It probably has more to do with the OD channel of the HRDx though as Its not really made for Uber Br000talzz Metulz.

alright, thanks man. i thought this would be it. i dont think my tubes have gone microphonic.
 
Re: tube amp squeal...

does it get worse when you move the guitar closer to the amp? Tube amps can do that, it's just feedback being exaggerated by the crazy gain.
 
Re: tube amp squeal...

One( or more) of your preamp tubes is microphonic. Replace the set with some tubes from tube depot. pay extra to have them checked for noise and microphonics.
 
Re: tube amp squeal...

does it get worse when you move the guitar closer to the amp? Tube amps can do that, it's just feedback being exaggerated by the crazy gain.

It isn't feedback. It's a squeal. When I set the drive to max on the dirtiest channel, it just squeals. if I play with the volume knob on my guitar, the squeal changes pitch.

I tried the tap test on my tubes, which did not make them cause any noise whatsover other than a tiny thud through my speaker.

all my tubes are glowing an orange-yellow color and my power tubes also glow slightly blue.

maybe I biased the amp too hot?
 
Re: tube amp squeal...

Nah power tubes glow slightly blue sometimes. It has to do something with the electrons and ions in the tube.
 
Re: tube amp squeal...

Okay..I know. You like single coils. You have an unpotted or noisy pickup. replace with new duncann . problem solved.
 
Re: tube amp squeal...

not all humbuckers are potted

I did not test with other guitars or cables, so I can't comment. This could prov the amp is fine.

I still feel like it has something to do with me using 16k resistance humbuckers on a dimed distortion channel.
 
Re: tube amp squeal...

my hot rod deluxe squeals when I set it to "more drive" and set the gain at maximum. I also have super high output humbuckers.


is it just too much gain? the only time it squeals is when I set it to extremes.
ya' think?
hmm- hi output pickups, the channel dimed- no wonder you get squeal.
Like the old joke- Doctor: does it hurt when you do that? then don't do that!
don't set it to extremes! the More drive channel on that amp is over the top anyway- don't dime that channel- seems to me you wouldn't get any note defintion with it dimed anyway.
 
Re: tube amp squeal...

There is always gonna be a limit at some point to how much gain you can use with a given guitar/ pickups/ pedals/ volume setting/ location/ location relevant to guitar etc. Sounds like you've found the limit.

Stick yer balls out and use less gain that you think you need. It will sound bigger out the front.
 
Re: tube amp squeal...

+1 on pickup and/or unpotted pickup cover microphony.

Q1) Does the pitch of the squeal change if you switch pickup?
Q2) Does the squeal change if you change the angle at which you are standing relative to the amplifier?
Q3) Is it worse with your Telecaster?

Guess what? Learn to control and/or exploit that squeal and you will finally be in business. Remember, Ted Nugent got famous using high gain amps and a hollowbody guitar.
 
Re: tube amp squeal...

Hi all,

This raises an interesting point:

I've been building and repairing amps for five years now, and am on the cusp of trying to market one model -- nothing big-scale -- just enough to support my hobby. In any case, I have a design --40W from 2 X EL34 -- mainly designed for clean headroom. (It stays pretty clean up to about 75%, and never goes beyond a toothy crunch.) With every control dimed, it will screach, but backing off on any one of several parameters will stop it -- treble, volume, master (if engaged), or preamp boost. Now, I COULD make various alterations that would prevent this, however, any such change will negatively impact (albeit marginally) the overall tone in more moderate settings.

My initial inclination concurs with the quote below: 'so,what did you EXPECT?'

On the other hand, the fact that people are asking the question, and are clearly concerned about the behavior suggests that can't be casually dismissed.

So, any thoughts from the consumer perspective would be gratefully appreciated.

Personally, I'm inclined to simply put a prominent acknowledgement in my user manual explaining the problem, and warning that: "if you do x, then y..."

I guess it's not a real big deal, but to me that's like fitting a Porsche with a throttle governor . . . ;^)

Thanks.

Joe


ya' think?
hmm- hi output pickups, the channel dimed- no wonder you get squeal.
Like the old joke- Doctor: does it hurt when you do that? then don't do that!
don't set it to extremes! the More drive channel on that amp is over the top anyway- don't dime that channel- seems to me you wouldn't get any note defintion with it dimed anyway.
 
Re: tube amp squeal...

If it's a really high pitch whistling sound, it could be a tube or some of the signal is feeding back to somewhere towards the input side of the circuit. When I modded my JVM, I didn't use shielded wire, and since I put the control pots next to the input (mistake on my part), it gives a high pitched whistle on higher gain settings. But others who put the controls in the same spot and use shielded wire don't seem to have that problem.

So I would try a known good 12AX7 in each preamp position, and if that doesn't fix it, I would look over a schematic and figure out where to try some shielding, or ask a tech.
 
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Re: tube amp squeal...

Hi all,

This raises an interesting point:

I've been building and repairing amps for five years now, and am on the cusp of trying to market one model -- nothing big-scale -- just enough to support my hobby. In any case, I have a design --40W from 2 X EL34 -- mainly designed for clean headroom. (It stays pretty clean up to about 75%, and never goes beyond a toothy crunch.) With every control dimed, it will screach, but backing off on any one of several parameters will stop it -- treble, volume, master (if engaged), or preamp boost. Now, I COULD make various alterations that would prevent this, however, any such change will negatively impact (albeit marginally) the overall tone in more moderate settings.

My initial inclination concurs with the quote below: 'so,what did you EXPECT?'

On the other hand, the fact that people are asking the question, and are clearly concerned about the behavior suggests that can't be casually dismissed.

So, any thoughts from the consumer perspective would be gratefully appreciated.

Personally, I'm inclined to simply put a prominent acknowledgement in my user manual explaining the problem, and warning that: "if you do x, then y..."

I guess it's not a real big deal, but to me that's like fitting a Porsche with a throttle governor . . . ;^)

Thanks.

Joe

Probably a layout or shielding issue. Look up layout issues concerning Trainwreck Express clones. It's one of those designs that are very finicky about the way they're laid out. Hope it helps.
 
Re: tube amp squeal...

yes, it's gain squeal.

get a noise gate or noise supressor if it really bugs you and you need to maintain those gain levels.

Otherwise just turn the gain down a bit. Benefit of that is increased clarity and probably a better front of house mix.
 
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