slight squealing/ticking sound from head

[surferdeac]

just received new stiletto ace head today. Been sound testing and trying to dial in some different tones to later work with. omfg I love this thing, but was wondering if anybody out there could shed some light on what seems to be a microphonic noise of some sort coming from the head and "not" the speakers. When in the "On" Mode of the ac Power switch and with either the amp on or just simply on standby, I hear
a slight squealing sound or almost like taking a metal fork and lightly rubbing it against say a commercial grade quarry tile. I would almost always say yeah it is a microphonic problem, but when using the amp in the "spongy" mode on the power switch that little squealing sound goes away. to anyone not familiar with this amp this mode (spongy} drops the plate voltage of the amp and maybe it draws less strain on the tubes as well. Maybe this could cause a slightly microphonic tube to become more microphonic. just left a message with an amp tech over at mesa but haven't heard from him yet. I want to play it so bad right now but want to get to the bottom of this first. I don't have any spare tubes at the moment so i don't want to trouble shoot it at the moment. anybody have any experience with this sort of head/situation. your insight would be appreciated. it sounds to me like the sound is coming from the area around v5 preamp tube maybe some to do with phase inverter bad filter capacitor????????? has anybody experience this PLEASE DROP A LINE
THANKS

 

[Anonymous]

congratulations on your new amp!!!!!!!

sounds like microphonic tube to me.... check that all the tubes are sitting properly on the sockets.

do you hear this noise on all channels?????? or just a specific channel produces this noise??

hope that helps :wink:

 

[surferdeac]

actually it occurs when the amp is in its regular mode meaning on. their is a "spongy on setting as well" it doesn't make this ringing/ticking noise as much in the spongy mode. I was concerned it was maybe some sort of hi voltage arc somewhere in the amp. that maybe would explain why it doesn't make as much ringing noise when in spongy setting because the plate voltage is lower. if an hi voltage arc creates a ticking/ringing noise in the amp head (not talking about the sound coming through speakers but the sound be made by the amp head itself) than maybe that would explain why ticking/ringing noise is reduced in spongy mode because the plate voltage is dropped in the head itself.

 

[thunda1216]

sounds like a bad preamp tube to me. to check, replace one at a time with a known good tube until you find the culprit. I had a bad phase inverter tube do this one time - a really shrill sound from the amp, not the speakers

ty

 

[surferdeac]

yeah thundal i thought the same thing, but i tried troubleshooting v5 preamp tube by swaping in and out my existing tubes in amp ex. v5 to v1 then v5 to v2 then v5 to v3 etc. and the sound continued to plague the amp. Is it possible that if there was a bad or should i say microphonic tube somewhere in the amp chain that it could possibly cause this no matter what v slot it was in??????????????????????????? Maybe i am over reacting the sound isn't extremely loud but its definitely there I talked to chris over at mesa and he told me that if in continued to bother me and or start to affect how the amp sounds through the speakers i should take it to the nearest repair station just to be safe. I played my amp last night for about 3 hours and the slight ticking/crackling noise continues to plague the head. If it were a bad phase inverter tube or maybe a bad circuit could i do extreme damage to my amp if i continued to ignore it it seeing it doesn't seem to affect the sound quality coming through the speakers??
PLEASE forgive me guys i am probably just anxious and worried about it seeing i just recieved this baby and waited about 7 months to recieve it
ROCK on EVERYONE !!!!!!!!

 

[surferdeac]

V5 is responsible for the phase inverter section correct??????????
or is it V4? maybe i troubleshooted the wrong preamp section wait a minute i should look this up i should have thought about this before i jumped to conclusions! : :shock:

 

[stokes]

You say it is coming from the chassis itself and not the speakers,when it is in standby.Does it ever come thru the speaker in play? A microphonic tube squeal would come thru the speaker.If the squeal isnt getting to speaker at all,I have some doubts about it being the tube,not to say it definately isnt,its just that microphonics manifest themselves at the speaker.I've had a few "new" amps come in with what appears to be a microphonic squeal only to find a bad filter cap in the preamp to be the cause.These IC and such brand caps seem to be crapping out quite a bit in the newer amps lately,I've never been a fan of the asian produced caps,but they seem to be worse than ever.Your amp is new,so I assume still under warranty.If so have an authorized service tech check it out,after you've discounted the tubes being the problem.Like someone already said,get a known to be good tube,and replace one at a time to see.You can also just pull the tubes one at a time,starting with V1,if the noise doesnt stop replace V1 and work your way to V5.If you pull a tube and the squeal stops,you will at least know which stage is causing it.That doesnt mean it is definately the tube,but just that stage,it could still be the filter for that stage.If after pulling and replacing all the preamp tubes the squeal didnt stop,you can assume its not a tube.In which case you should get it to a tech,if it is one of the filter caps you want it changed before it self destructs.

 

[surferdeac]

thanks stokes for your input ya know i know it sounds crazy to me that they wouldn't catch a bad filter cap before shiping it out seeing that the noise was evendent when i did my first sound check. that being said i just recently discovered that when if i wrap my hand around the rectifier tube before it has a chance to get to hot while on standby, the ringing vibrating sound i hear seems to subside maybe the rectifier tube is making some sort of ringing vibrating sound / characteristic. no one ever seems to say anything about power tubes making weird vibrating sounds maybe it some its some sort of weird electrical harmonic sound that is tied somehow to the rectifier tube section and by wraping my hand around the tube it muffles the either tube harmonic/ringing vibration or silences an electrical harmonic sound of some sort. :idea:

 

[R_ADKINS80]

Ya know now that you mention it.....My Mesa big bottle 5U4G rectifier tubes rattle. My NOS =C= black plates do not, nor do any of my small bottle 5U4GB's or my Sovtek 5AR4's. If you have the big red base mesa rectifier tubes then I bet thats your answer. Mine work just fine but have ALWAYS rattled.

 

[stokes]

A "rattling" rectifier tube shouldnt get to the speaker,it isnt in the signal chain.Assuming the noise doesnt get to the speaker,you havent made that point clear yet,I would say to try a different rectifier tube.Get your self a good NOS,the current production tubes suck out loud,by comparison.Even used old stock tubes are better than the crap they are making today.As for "not finding a bad filter cap before shipping it out" I can only say,you give them way too much credit.In my opinion they send all their amps out with "bad" filter caps.Not just Mesa but Fender even more so,and just about every manufacturer.In my experience,all those IC and xicon etc. caps suck,period.I just had a guy bring me a Hot Rod Deluxe that was only a couple of months old just to look at it and offer advice to make it sound better.He is actually a close friend,so I recomended getting all those asian caps out and replaced them with F&T's.He was absolutely blown away by the improvement in response and how much the amp tightened up.The caps that were in the amp originally all "tested" fine for leakage and capacitance,but the only real "test" is in your ears.

 

[surferdeac]

Thank you very much stokes and R_adkins80 for your input
No Stokes the noise doesn't get to the speaker. its just a noise that is being made by my brand new stiletto ace head. its a ringing/vibrating/ticking sound that seems to be coming from the rectifier tube i think or somewhere in the chasis underneath the area of the rectifier tube. When i wrap my hand around the tube that ringing/vibrating/ticking sound subsides. The sound itself doesn't bother me one bit when playing but i was just concerned that there could be something wrong with the head. I have a 5U4GB mesa boogie Stock rectifier tube in my ace head. Ya know i have logged about 15 solid hours of moderate volume playing on this amp head and this sound that the head or possible rectifier tube is making hasn't gotten any worse. Maybe a 5U4GB rectifier tube is more likely to make quirky noises in ace heads considering they are being used in an el34 based amp that has a high plate voltage.
THAKS ONE AGAIN GUYS FOR YOUR INPUT it has helped bring me a little piece of mind concerning this particular issue.

 

[stokes]

I am willing to bet a good NOS rectifier tube wouldnt make the noise.It has nothing to do with the EL34's or the high plate voltage,it is the crap current production tube.NOS 5U4's are still plentiful and cheap enough,take a look on eBay.Like you say,it doesnt get to the speaker so it isnt a major concern,but it is an indication of the tubes components "moving" or not being tight enough,since tubes dont have moving parts it will certainly affect the tubes life span.

 

[surferdeac]

Thanks once again stokes !!!!
Do you know if mesa carries NOS 5u4's rectifier tubes. At least they don't advertise that they do. I guess i could call chris over at mesa and ask anyway. hopefully he doesn't say ah no and if you use one it will void your amps warranty. I don't know why they wouldn't search out some of these other tubes that i know work just fine with their amps. They charge you an arm and a leg for some of their stock tubes anyways and a lot of people i have talked to have stated that their are other tubes out their that work just fine and even better as long as they are matched and within the tolerance ranges of the various Mesa Heads.

 

[stokes]

A rectifier tube requires no matching or special grading.And no,Mesa only carries current production stuff.If they dont know you put a different rectifier in the amp it wont void the warranty,so if you ever had to send it for warranty work,just put the old stock tube back in.They will be none the wiser.The main reason they dont "search out some of these other tubes"is purely a marketing thing.Profit margin is their bottom line.The whole idea behind their "magical fixed bias thing" is so you have to buy tubes they import and grade to match their pre-set fixed bias,which,by the way doesnt mean non-adjustable.I have seen tubes they sell that are supposedly selected to match the last set you used of the same "grade" vary by 10 or more ma's,which usually means a big difference in the tone you get.With other amps you match your amps bias to whatever tubes you happen to buy,with them you have to use tubes they select to operate within the parameters they set or you "void the warranty".So dont be afraid to "void your warranty" by using a tube that will work better,like I said,just put the noisy tube back in if you ever have to send it back to them.They were having problems with the 5Y3 rectifiers in the Lonestar,it would fry quite fast in the full power mode.They would send you a new crap 5Y3 when it happened,but if you use a tube that wont fry,like a NOS 5Y3 or a 5V4 you void your warranty.Guess they purchased way too many low grade 5Y3's.I'll bet when the supply finally runs out they will stop sending replacements and allow you to use a good tube.So go get a good tube that wont sound like an old clock ticking and save the noisy one just in case.You'll feel better knowing you dont have a rectifier that is about to fail.I would even use a used old stock 5U4 before using a Sovtek or whatever crap they are peddling.

 

[surferdeac]

thanks once again stokes for your thoughts

ROCK ON :mrgreen: :twisted:

 

[surferdeac]

i just recently discovered that when if i wrap my hand around the rectifier tube before it has a chance to get to hot while on standby, the ringing vibrating sound i hear seems to subside maybe the rectifier tube is making some sort of ringing vibrating sound / characteristic. no one ever seems to say anything about power tubes making weird vibrating sounds maybe it some its some sort of weird electrical harmonic sound that is tied somehow to the rectifier tube section and by wraping my hand around the tube it muffles the either tube harmonic/ringing vibration or silences an electrical harmonic sound of some sort. :idea:

The rectifier tube was the culprit. I bought a new one from mesa and bye bye strange ringing noise also bought a pair of str 450's for my baby.
Life is good :twisted: