EVH acting up again

[Coma]

Here's a little something for the more electrically versed of you to bite into: My 100w EVH 5153 gets a real nasty squeal on the red channel once the volume knob passes 9 o'clock, with gain around 1 or 2 o'clock.

If the amp is moved to a separate room from the speakers there's no squeal and I can crank it no problem. My first thought was microphonic preamp tube(s). I've tried replacing them and the noise persists. I've swapped between three different tubes in the 1st position for the red channel, and the noise persist. If I do the ol' chopstick test I get a lot of thumping type noise coming through the speakers, but no ringing or pinging.

I've handed it over to a tech, he says he can't find anything wrong with it.

If I plug a guitar straight into the amp, with the guitar volume knob at zero, there's no squealing. With the guitar volume up, the amp starts squealing once the amp volume hits 9 o'clock. If I connect any of my pedals in between guitar and amp, with pedals powered but turned off, and guitar volume at zero there's no squeal. BUT if I hook up my Boss NS2 with the 4 cable method the amp starts to squeal once amp volume is turned up (even with guitar volume at zero and pedal turned off). I even borrowed a friend's NS2 for comparison and it's the exact same problem.

I've had the NS2 and amp since 2012 or so and I can't recall having these issues prior to last fall or so. The squeal could be feedback, but it's very high pitched and intensive. It doesn't really sound like when you're playing too close to your amp and you let the guitar feed back into it.

Any idea if there's anything I should look for? I'm contemplating having another tech look at it but it feels kinda stupid.

[JMP/HBE]

Re: EVH acting up again

Here's a little something for the more electrically versed of you to bite into: My 100w EVH 5153 gets a real nasty squeal on the red channel once the volume knob passes 9 o'clock, with gain around 1 or 2 o'clock.

If the amp is moved to a separate room from the speakers there's no squeal and I can crank it no problem. My first thought was microphonic preamp tube(s). I've tried replacing them and the noise persists. I've swapped between three different tubes in the 1st position for the red channel, and the noise persist. If I do the ol' chopstick test I get a lot of thumping type noise coming through the speakers, but no ringing or pinging.

I've handed it over to a tech, he says he can't find anything wrong with it.

If I plug a guitar straight into the amp, with the guitar volume knob at zero, there's no squealing. With the guitar volume up, the amp starts squealing once the amp volume hits 9 o'clock. If I connect any of my pedals in between guitar and amp, with pedals powered but turned off, and guitar volume at zero there's no squeal. BUT if I hook up my Boss NS2 with the 4 cable method the amp starts to squeal once amp volume is turned up (even with guitar volume at zero and pedal turned off). I even borrowed a friend's NS2 for comparison and it's the exact same problem.

I've had the NS2 and amp since 2012 or so and I can't recall having these issues prior to last fall or so. The squeal could be feedback, but it's very high pitched and intensive. It doesn't really sound like when you're playing too close to your amp and you let the guitar feed back into it.

Any idea if there's anything I should look for? I'm contemplating having another tech look at it but it feels kinda stupid.

I would expect nothing less from a massed produced amp made in Mexico.
Try the gate in front or in the loop if you havent.

Try a different guitar.
Impossible for me to know whats going on from here.

[Coma]

Re: EVH acting up again

I would expect nothing less from a massed produced amp made in Mexico.
Try the gate in front or in the loop if you havent.

Try a different guitar.
Impossible for me to know whats going on from here.

Not sure what being made in Mexico has to do with it, but I've tried three different guitars (same squeal) and I've tried the pedal just in front of the amp (no squeal with guitar volume down) and I've tried it with X-pattern connection both with FX loop engaged and bypassed (same squeal both times, even with guitar volume at zero).

[JMP/HBE]

Re: EVH acting up again

Not sure what being made in Mexico has to do with it, but I've tried three different guitars (same squeal) and I've tried the pedal just in front of the amp (no squeal with guitar volume down) and I've tried it with X-pattern connection both with FX loop engaged and bypassed (same squeal both times, even with guitar volume at zero).

ah well MIM means its prone to having problems like yours because its not well made.
A video would help as random typing is going nowhere.

Could be a ton of things.

When you say X-pattern i have no clue what you're talking about.

If you think EVH products are quality because the have Ed's initials here's some info for you : Ed always makes his products on the cheap as he doesn't care what he puts his name on to make a buck.
And he wears out his welcome with one company & hippity-hops to another to anyone who will pay him money & market his stuff.
That is NOT the definition of a "great product".

[chadd]

Re: EVH acting up again

It would be a lot easier to help diagnose if we could hear it.

Not sure what being made in Mexico has to do with it...

Absolutely nothing, but some people have to be condescending.

[dave74]

Re: EVH acting up again

X-pattern is connecting the NS2 both in-front and in the loop at the same time. Good to try as many things as you can think of.

[JMP/HBE]

Re: EVH acting up again

It would be a lot easier to help diagnose if we could hear it.


Absolutely nothing, but some people have to be condescending.

Im sorry but in 2020 if people in general see no difference between a 60's/70's JMP Marshall or a made in USA MESA product compared to a Mexican or Chinese made amp/product there is no hope for future generations of musicians.

[FuseG4]

Re: EVH acting up again

You can try chopsticking components and wires downstream of the gain tube and see if a there's something like a solder joint or something that vibrates when amp gets going

Dirty tube sockets and loose connections can cause squeals
Loose or bad ground connections
Wires in the wrong spot can cause even oscillations that might present as a squeal
Bad filter caps can cause but you say your tech didn't find anything

Anything mass produced of any price point can have issues go look on boogie forums and see that people have a ton of issues and it doesn't matter where it's made...

Anyways good luck sorry to hear about your troubles

[ErikH]

Re: EVH acting up again

What happens if you turn the gain down? Does the squeal go away? What is nothing is plugged in to the amp at all (aside from the speaker cabinet), does it still squeal?

[Rex_Rocker]

Re: EVH acting up again

Did you try a different preamp tube in the FX loop driver spot? My LBX is particularly sensitive to microphonic tubes in that spot. Maybe that explains why it squeals with the NS-2 in the loop.

And Mexican-made EVH amps are well built.

[Coma]

Re: EVH acting up again

What happens if you turn the gain down? Does the squeal go away? What is nothing is plugged in to the amp at all (aside from the speaker cabinet), does it still squeal?

If I reduce the gain, I can crank the volume higher before it starts to squeal.
It does not squeal with nothing plugged into it, same as with a guitar with volume at zero.

[Coma]

Re: EVH acting up again

Did you try a different preamp tube in the FX loop driver spot? My LBX is particularly sensitive to microphonic tubes in that spot. Maybe that explains why it squeals with the NS-2 in the loop.

And Mexican-made EVH amps are well built.

That tube seemed fine when I tapped it, but that's a good point, I haven't looked at it. I'll try swapping it tomorrow. That being said, it doesn't cause a fuss with any other pedal in the loop. In fact, when I bypassed all pedals that are in front of the amp and just ran it with the ones that are in the loop (sans NS2, that is) there was no squeal (with guitar volume down, that is).

[ErikH]

Re: EVH acting up again

This sounds like a classic V1 problem. Try a different 12AX7 in V1 or try a lower gain preamp tube. The red channel is pretty scorching. If changing V1 doesn't do it, try V2, then V3 and so on.

[PDC]

Re: EVH acting up again

I had a similar problem with a long-since sold Mesa Mark-III. Sounds crazy, but it ended up being a bad cable between the lead/rhythm foot switch and the foot switch input on the amp. Still haven’t figured out exactly how that caused the problem, but it did. Also might try swapping your guitar cable and the speaker cable. I have had cheaper guitar and speaker cables ‘function’ as in no identifiable shorts, but demonstrate a much lower threshold for squealing and noise as you turn up the gain and the output.

[JMP/HBE]

Re: EVH acting up again

That tube seemed fine when I tapped it, but that's a good point, I haven't looked at it. I'll try swapping it tomorrow. That being said, it doesn't cause a fuss with any other pedal in the loop. In fact, when I bypassed all pedals that are in front of the amp and just ran it with the ones that are in the loop (sans NS2, that is) there was no squeal (with guitar volume down, that is).

Sounds like a pedal or guitar pickup problem to me, not amp. You just said the amp is fine with no pedals in front. That should tell you something.
Are your pickups wax potted ?
Are you using a boost pedal ?

I must say its hard to formulate an overall view of whats going on because you're kind of ambiguous in your selective descriptions.
Prolly not intentional but confusing none the less.