What's that noise! EVH 5150 III 50W weird ringing.

[isoP]

Hi,

Can anybody identify this strange ringing noise that's coming out of my amp head? It seems to appear when lower tones resonate and everything kind of vibrates. I can also produce the sound by slightly hitting the top of the head. Is it a tube? Or is something mechanical loose in there?

Any help is greatly appreciated.

- Pyry

 

[newholland]

microphonic tube.. you have a bad preamp tube. open it up, and tap all your tubes gently with a wood pencil- when one makes that noise, replace the offender. happens a lot.

check your power tubes too- theyll do similar things- but id suspect preamp tubes first

 

[isoP]

Thank you! Is it simple to fix, just locate the broken tube, replace it and continue playing?

 

[newholland]

Thank you! Is it simple to fix, just locate the broken tube, replace it and continue playing?

Generally, yep. Depending on how much you use it and how hard- tubes do need replacing periodically. on a 50 watter for quiet home use you can get away with mebbe every other year, mebbe three.. but ive had el84 amps i ran banding i retubed the power section twice a year and preamps maybe every year or two.

when they go microphonic though, which just happens, its usually just a quick swap.

 

[isoP]

Thanks again. I've actually had this amp for over ten years for gigs and recording regularly, but never had a tube issue so far. It had to happen some time, I guess.

 

[isoP]

Hi again!

Could I ask for a second opinion on the tubes, please? I'm fairly certain that preamp tubes #2 and #3 are both microphonic, but what about the first power tube? Thanks!

 

[newholland]

Hi again!

Could I ask for a second opinion on the tubes, please? I'm fairly certain that preamp tubes #2 and #3 are both microphonic, but what about the first power tube? Thanks!

if its ten and has never been changed, tbh, id redo the entire amp top to tail myself.

power tubes absolutely, if thats audible through the speaker, but you always do BOTH power tubes and buy them in a matched set.

 

[laxu]

Hi again!

Could I ask for a second opinion on the tubes, please? I'm fairly certain that preamp tubes #2 and #3 are both microphonic, but what about the first power tube? Thanks!

Preamp tube #3 clearly sounds microphonic, so I'd just swap that and see if that solves your issue. #2 seems fine to me, at least I can't hear it in the video. Because of the way they are mounted on the chassis they may sound a bit different when you tap on them.

It's very possible the power tubes are due a change too so swapping both is not a bad idea.

Depending on how much you use it and how hard- tubes do need replacing periodically. on a 50 watter for quiet home use you can get away with mebbe every other year, mebbe three.. but ive had el84 amps i ran banding i retubed the power section twice a year and preamps maybe every year or two.

I think those are pretty pessimistic numbers for an amp used mainly at home. I'd just keep using it as long as now issues show up.

But obviously amps are not built equal, some run very hot and can eat tubes.

 

[Pissedplexi]

Been 10 years since a retube. Change them all and bring it back to life. I get changing the ringers(noisy ones)but I can’t leave the thread without recommending a full retube after that amount of time. If they been changed ignore this.

 

[newholland]

Preamp tube #3 clearly sounds microphonic, so I'd just swap that and see if that solves your issue. #2 seems fine to me, at least I can't hear it in the video. Because of the way they are mounted on the chassis they may sound a bit different when you tap on them.

It's very possible the power tubes are due a change too so swapping both is not a bad idea.


I think those are pretty pessimistic numbers for an amp used mainly at home. I'd just keep using it as long as now issues show up.

But obviously amps are not built equal, some run very hot and can eat tubes.

oh definitely. the studio .22 i had was an absolute tube destroyer, and that one got played LOUD a lot at the far fringes of its capacity. my 50-60 watters do not these days- and its pretty normal to see 3-4 years on tubes if i let em go a while- and two other ampsll divvy the load now too.

all depends how much ya play!

ten years though.. even a home use amp id redo that thing

 

[isoP]

Thanks for the insight everybody! I ended up ordering all seven new preamp tubes and decided to take care of the 6L6's on a slightly later date. Can't wait to bring it back to life.

 

[newholland]

Thanks for the insight everybody! I ended up ordering all seven new preamp tubes and decided to take care of the 6L6's on a slightly later date. Can't wait to bring it back to life.

cool cool- my bets are, with a few hours on it- youre gonna be psyched! just keep in mind that when power tubes go, it can be an expensive repair, so definitely plan on it. the bench fee for a coupla burnt 50 cent resistors is no joke.

if the amp starts acting weird, losing sound or being fritzy- shut it down and get those in ASAP. most of the times if they start doing weird stuff and go, your fuses will help save you- but ive certainly had the tubes go, and the fuse DID NOT. just tryna keep you outa the weeds.. and that $100 bench fee sucks on top of $100 power tubes.

 

[Karl Houseknecht]

Fox what’s broken and go back to playing. There’s no need for a complete retube. Most folks replace tubes too frequently. When you need power tubes, you’ll know it.

 

[newholland]

Fox what’s broken and go back to playing. There’s no need for a complete retube. Most folks replace tubes too frequently. When you need power tubes, you’ll know it.

and you'll pay for the luxury of ignoring readily available signs, like lots of microphonic tubes. believe me, theres nothing worse than letting the smoke out because 'ill just go a little longer'.

this amp has had the same tubes for a decade, and im gonna guarantee theyre not old stock RCAs, so theyre not like finding an old fender.

not to say you're wholly wrong about people swapping tubes- but im pretty close to sure you're wrong in this sitch. watch the video he posted, and see if you deduce its overkill.

 

[Pissedplexi]

Fox what’s broken and go back to playing. There’s no need for a complete retube. Most folks replace tubes too frequently. When you need power tubes, you’ll know it.

I don’t think this scenario fits too frequently. Plus he’s learning about microphonics(noisy tubes)and maybe learn how to bias an amp?

Personally I would never go to a tech for a tube change or bias. This is normal tube amp maintenance. Excluding fear of electricity. There’s always cathode biased amps. Plug and play.

Wait till he wants to tube roll. Now there’s a can of worms.lol

 

[mbenigni]

I've said it before and I'll say it again: some of you guys change your tubes more often than I change my strings.

 

[isoP]

Yeah, generally my philosophy is to fix things only when they get broken, but I figured that even if only one tube has gone bad, the rest are just as old and most likely will also go sooner rather than later. It's just like replacing each old string at the same time even though just one broke - it just makes sense. Changing tubes once a decade isn't that bad.

 

[newholland]

I've said it before and I'll say it again: some of you guys change your tubes more often than I change my strings.

aw man, i cannot be further from this truth. ill extract as much juice from mine as i can, but at some point after my second amp flashed in my face, i lost the taste for paying twice or more the cost of tubes to bench an amp.

not that techs dont deserve my money, but id rather keep playing and buy TWO sets of power tubes over running a set to the bitter end to extract that last 5% of life. just seems like bad money after good.

at some point its just changing your oil after the engine seizes.

 

[Pissedplexi]

I've said it before and I'll say it again: some of you guys change your tubes more often than I change my strings.

I hate changing strings. It’s like cleaning your room as kid. It’s a chore.