|
Post by tjstrat on May 8, 2006 14:56:11 GMT -7
... in my 38 Studio Lead. Happens whether I'm using effects loop or am running straight in. It seems to come in waves and sounds like an electronic version of a wind rippling a canvas sail or a flag... It pops, then subsides, then rises again.
Not present in any of my other amps, so although it may be the bad power in my basement, I'm wondering if I should just replace all the tubes and see. Does this sound like a tube failing or something arcing somewhere?
|
|
|
Post by cementman on May 8, 2006 16:49:30 GMT -7
got to be one of them there preamp tubes.. my z had a bad reverb tube, it hissed, put a better one in there and it went away. less than 20 dollar fix. mine has a low rumble pop after i turn on the standby (comes through the speakers once then goes away) but the amp sounds great so i dont care...
|
|
|
Post by guitarboy02451 on May 13, 2006 19:09:38 GMT -7
time to re-tube... If you have more than 600 hours on the power tubes, it's time to replace the quartet of EL84's. Wouldn't hurt to swap out the 12ax7's... unless you got a ton of $$$ in NOS tubes.
pg
|
|
|
Post by mothy on Jun 9, 2006 8:47:57 GMT -7
Finally someone with the same problem as me. I traced it to the 12AT7 tube in the 3rd preamp slot. It stopped when I replaced it and then a few weeks later, magically came back and will not stop no matter how many times I replace tubes.
any input is welcome.
|
|
|
Post by myles on Jun 9, 2006 9:48:18 GMT -7
time to re-tube... If you have more than 600 hours on the power tubes, it's time to replace the quartet of EL84's. Wouldn't hurt to swap out the 12ax7's... unless you got a ton of $$$ in NOS tubes. pg The preamp tubes will generally last many years. On the output tubes on this amp I notice a very big change going to a fresh set in 300 hours or even less.
|
|
|
Post by myles on Jun 9, 2006 9:49:30 GMT -7
Finally someone with the same problem as me. I traced it to the 12AT7 tube in the 3rd preamp slot. It stopped when I replaced it and then a few weeks later, magically came back and will not stop no matter how many times I replace tubes. any input is welcome. Which 12AT7 are you using? I have found many of these which are current production that are way out of original spec and can overheat very dramatically.
|
|
|
Post by mothy on Jun 9, 2006 9:56:19 GMT -7
Myles, thanks for writing. I used a NOS Mullard. Great sounding, warm, etc. When the noises returned last night, I swapped it for another NOS Mullard...same thing right off the bat. Then I put in a JJ eec81. The noise stopped temporarily but I could still coax them out after a good peroid of warming up. Tim
|
|