TemporarilyStairs
Well-known member
Bah, figured it was too good to be true.
I recently dug out my old Mesa Quad, that was sitting in the basement for a few years. I shelved it initially because I was having some intermittent issues with it, and I got tired of lugging the rack around
Well anyway I dug it out, popped some new tubes throughout, and voila, it was working beautifully. It kept doing so for about a week with a couple hours of daily play on it. I go to fire it up today, and... yeowch, there's the issues again.
What happens is essentially that the output from the preamp gets cut to a fraction of what it should be, couple with a massive loss of low end output particularly (sounds like a damned high-pass filter heh) This sounds strange in the lead channels, but Rhy 1 suffers even more.... it sounds weak, but the fun part is the breakup it gets, which sounds like a cat is hiding in my cab scratching his claws across pieces of tinfoil. The breakup appears to be related to the normal operation of it, that is, lowering the volume on Ch1, guitar, etc. almost entirely gets rid of it. I don't know if that could be relevant, but I have a feeling it might be.
This seems to happen intermittently, (and it goes away without warning, much to the chagrin of my eardrums and my cat) on the top set of outputs (A? 1? Whatever) but I just discovered today that it seems to consistently be happening on the second one. I may just not have given it enough time, of course.
When it first started doing this years ago, I figured it had to be a tube issue. Part of the reason I gave up on it entirely was that I replaced the tubes, twice, tested them in other amps, etc.. Every time I asked an amp repair shop about it, they basically just explained that I'm a moron and it's just a tube problem. Two, after I explained that I tried retubing it, said "Don't bother bringing it in." So much for customer service.
The fact that it has weird, similar issues across all channels probably helps narrow down the cause pretty good. Given the age, and nature of the issue, my idiotic guess would be a capacitor issue. Anybody that can shed light on that?
Basically, I'm hoping either A)somebody here might have a good suggestion as far as places to ask around or whatnot, or B)somebody here is a genius and tells me how to fix my amp with two rubberbands, a dime, and a bendy straw. Or, they knew the preamp well enough to try to help me figure out what's up.
Basically I just hoped that there might be somebody who could help try to get me closer to diagnosing the problem without the fact that I know very little about electronics helping some tech convincing me that I need $800 worth of replacement parts in addition to rotating my tires and replacing a serpent belt
Also, if anybody around Chicago has any recommendations about amp repair shops/techs, I would love to hear it. There's a shop right by me that (i'm just learning now) has recently started doing work on amps and is apparently a licensed Boogie shop too, so I might check them out, but I just want to know as much as I can before I commit to anything.
Sorry for the long post... brevity is not my strong point. Thanks in advance all
I recently dug out my old Mesa Quad, that was sitting in the basement for a few years. I shelved it initially because I was having some intermittent issues with it, and I got tired of lugging the rack around
Well anyway I dug it out, popped some new tubes throughout, and voila, it was working beautifully. It kept doing so for about a week with a couple hours of daily play on it. I go to fire it up today, and... yeowch, there's the issues again.
What happens is essentially that the output from the preamp gets cut to a fraction of what it should be, couple with a massive loss of low end output particularly (sounds like a damned high-pass filter heh) This sounds strange in the lead channels, but Rhy 1 suffers even more.... it sounds weak, but the fun part is the breakup it gets, which sounds like a cat is hiding in my cab scratching his claws across pieces of tinfoil. The breakup appears to be related to the normal operation of it, that is, lowering the volume on Ch1, guitar, etc. almost entirely gets rid of it. I don't know if that could be relevant, but I have a feeling it might be.
This seems to happen intermittently, (and it goes away without warning, much to the chagrin of my eardrums and my cat) on the top set of outputs (A? 1? Whatever) but I just discovered today that it seems to consistently be happening on the second one. I may just not have given it enough time, of course.
When it first started doing this years ago, I figured it had to be a tube issue. Part of the reason I gave up on it entirely was that I replaced the tubes, twice, tested them in other amps, etc.. Every time I asked an amp repair shop about it, they basically just explained that I'm a moron and it's just a tube problem. Two, after I explained that I tried retubing it, said "Don't bother bringing it in." So much for customer service.
The fact that it has weird, similar issues across all channels probably helps narrow down the cause pretty good. Given the age, and nature of the issue, my idiotic guess would be a capacitor issue. Anybody that can shed light on that?
Basically, I'm hoping either A)somebody here might have a good suggestion as far as places to ask around or whatnot, or B)somebody here is a genius and tells me how to fix my amp with two rubberbands, a dime, and a bendy straw. Or, they knew the preamp well enough to try to help me figure out what's up.
Basically I just hoped that there might be somebody who could help try to get me closer to diagnosing the problem without the fact that I know very little about electronics helping some tech convincing me that I need $800 worth of replacement parts in addition to rotating my tires and replacing a serpent belt
Also, if anybody around Chicago has any recommendations about amp repair shops/techs, I would love to hear it. There's a shop right by me that (i'm just learning now) has recently started doing work on amps and is apparently a licensed Boogie shop too, so I might check them out, but I just want to know as much as I can before I commit to anything.
Sorry for the long post... brevity is not my strong point. Thanks in advance all
