More 5150 problems.....

[WarMachine]

Well, a bit back i had posted a thread asking about the possibility of the tubes going bad in my 5150, so i got a bonus from work (yay me ) and got a full tube set from dougstubes (the metal tube set). So i put em in and it just sounds beyond amazing, never sounded any better....but after about an hour of recording i get a God awful screech coming from it. No fellas, not guitar feedback lol, the best way i could describe it is a super high pitched balloon deflating with some distortion, no matter what volume the amp or guitar was on, no matter if i was plugged in it still made that screech. Could that possibly be a fuse or one of the tubes? Also, just for my own piece of mind i played with the EQ and res/pres controls and they worked, it just changed how that screech sounded. I wouldn't assume it was a tube since these are not even a day old with just an hour of use but then again im a noob when it comes to tubes and troubleshooting them. Do you guys have any ideas as to what it could be?

 

[Vostre Roy]

I'd guess for a microphonic issue from one of the preamp tubes. Do you have the old ones, so you could swap them one by one to see if the problem is there?

 

[WarMachine]

Shit, that's what i was afraid of Yeah dude i kept all my old ones so i'll try it out when i get off work. I forgot to mention that after i left it off for about 10-15mins i turned it on, let it warm up and jammed for a couple of minutes and it sounded killer again, no weird screeching. If a tube is going microphonic would it be hit and miss like that or should it be more of an all the time thing? The thing that sucks is that it'll be a bitch finding out which one it is since it happened after all the tubes got hot after about an hour. When i try this out should i leave the amp unplugged for a while or can i swap them out as soon as i turn the power off? Sorry for all the questions dude lol, i've just heard all the horror stories associated with getting fried (and not the good kind of fried) from tube amps Thanks for all your input dude

EDIT: Also forgot to mention, when i was messing with it when i got the weird sounds i tried playing to just see how it sounded and it sounded like i was running the drop tune settings on a digitech whammy if that helps with the troubleshooting lol.

 

[glpg80]

Intermittent problems are not tube related. Either tubes are bad or they aren't. They definitely do not have a mind of their own

It is most definitely something else that is serious. Doug burns in all of his preamp tubes that are high gain to weed out the ones that are bad. I highly suggest taking your amplifier to a tech to get checked out for the intermittent problem. It is not tube related, is preamp related, and is not preamp tube related.

 

[WarMachine]

..................shit

I was hoping not to hear that lol. I didn't really figure a tube would do that, but as you said either be bum or not. That sucks just when i was thinking that amp was sounding brutal as it ever had at that lol. Thanks for the info guys, guess its time to take it to my tech

 

[GoldDragon]

Burning in a tube cannot guarantee its not microphonic. Just swap out the tubes to find which one it is and get a replacement.

 

[vick1000]

When it's happening, press on or wiggle the preamp tubes one by one, it's a known issue on some of the preamp boards (the board where the preamp tubes plug into).

 

[glpg80]

Burning in a tube cannot guarantee its not microphonic. Just swap out the tubes to find which one it is and get a replacement.

Very true, but the amplifier was in questionable state to begin with. Remember that the sockets are directly board mounted on 5150's and by pressing/changing them out, a cold solder joint may be to blame hence the intermittent attitude.

If the amplifier can be made to do it again with the old tubes then it is most definitely not tube related.

 

[WarMachine]

If it's a bum tube would wiggling the tube make it stop or make it start screaming louder or would it stop? I'm just asking to know what i should be listening for.

 

[WarMachine]

Very true, but the amplifier was in questionable state to begin with. Remember that the sockets are directly board mounted on 5150's and by pressing/changing them out, a cold solder joint may be to blame hence the intermittent attitude.

If the amplifier can be made to do it again with the old tubes then it is most definitely not tube related.

I'll give that a shot as well before taking it to my tech. I can say that it never happened like that with the old tubes in it. All it would do with the old set was at times the presence and resonance would completely drop out, just like you walked up to it and turned them both to zero. When that happened i tried slowly turning them both up from zero to 10 and the tone didn't change at all. When i swapped the old tubes for the new set it just screamed.....then, it screamed some more, but in the bad way this time lol.

 

[espmetalhead]

lightly tap on each pre amp tube with the eraser end of a pencil while the amp is on, the bad one will be super noticeable.

 

[WarMachine]

Thanks dude, i'll give it a shot!

 

[SandyRavage]

Dude had the exact same thing happen in my ultra, tubes were burnt in and I was around 15-20 hours or so into the new set and it was whistling and wailing like you wouldn't believe.

It's been almost a year now and not a hiccup since replacing the bad tube.

 

[Spinedriver]

That's why you need to get yourself a nice solid state head like a Randall or Blackstar. None of that voodoo-tube hoob-a-joob to deal with.

 

[glpg80]

That's why you need to get yourself a nice solid state head like a Randall or Blackstar. None of that voodoo-tube hoob-a-joob to deal with.

 

[vick1000]

That's why you need to get yourself a nice solid state head like a Randall or Blackstar. None of that voodoo-tube hoob-a-joob to deal with.

That explains it, you didn't cut the head off a fertiel chicken, and butcher a sterile goat, before you put the new tubes in, did you?

 

[Leuchty]

That's why you need to get yourself a nice solid state head like a Randall or Blackstar. None of that voodoo-tube hoob-a-joob to deal with.

That explains it, you didn't cut the head off a fertiel chicken, and butcher a sterile goat, before you put the new tubes in, did you?

My god...

 

[WarMachine]

That's why you need to get yourself a nice solid state head like a Randall or Blackstar. None of that voodoo-tube hoob-a-joob to deal with.

So.... you're saying "we don need nah steeeking toobs!"

lol well i do
Another bit of good news....guess its just my time for ALL my shit to .... up. I was jamming at practice yesterday and my Rocktron V300 just shut off....and didn't power back up...for the rest of the night. yeah, coolness

 

[GoldDragon]

I'll give that a shot as well before taking it to my tech. I can say that it never happened like that with the old tubes in it. All it would do with the old set was at times the presence and resonance would completely drop out, just like you walked up to it and turned them both to zero. When that happened i tried slowly turning them both up from zero to 10 and the tone didn't change at all. When i swapped the old tubes for the new set it just screamed.....then, it screamed some more, but in the bad way this time lol.

I think before you had bad power tubes, now one of the new preamp tubes is microphonic.

 

[WarMachine]

Thanks man, all suggestions are more than welcome lol. hopefully i'll be able to have more time to jam on it later today and if so i'll put a mic in front of it and record the sound so you guys can hear what im talking about. hopefully it is a tube, cheap easy swap. but i agree with glpg80, i've heard nothing but good things about dougstubes thats why i went with him, but stranger things have happened.