Clean channel breaking up. Not in a good way.

dreadguard268

New member
The clean channel on my single rec decided that it was going to put out some really nasty noise whenever I did anything more then slightly touch a single string. It sounded as if it were breaking up but did so in a nasty sounding way. I switched over to the dirt channel to see if anything was wrong there as well and it seemed to me that it wasn't coming out quite right. I'm not entirely convinced that I wasn't just hearing things for that though.

Any thoughts?

This was my first tube amp and I purchased it used I think 2 years ago. I have not replaced any of the tubes yet. Mainly because even after researching it I'm not sure that I'm 100% on the signs of tubes needing replacement.
 
Re: Clean channel breaking up. Not in a good way.

If it's only happening on one channel it's a preamp tube. The manual should tell you which tube(s) are used in the clean channel. Replace that/those first.
 
Re: Clean channel breaking up. Not in a good way.

did you say it was on both channels though ? I had this same problem and it was my power tubes so I would change those first and go from there , Preamp tubes last longer than power amp
 
Re: Clean channel breaking up. Not in a good way.

did you say it was on both channels though ? I had this same problem and it was my power tubes so I would change those first and go from there , Preamp tubes last longer than power amp

I'll have to go back to it and try it again. I'm not entirely convinced that I wasn't just making myself think it was off. I may just change the power tubes and go through the manual see which tube governs the clean and change that as well. Can't really hurt can it?
 
Re: Clean channel breaking up. Not in a good way.

I'll have to go back to it and try it again. I'm not entirely convinced that I wasn't just making myself think it was off. I may just change the power tubes and go through the manual see which tube governs the clean and change that as well. Can't really hurt can it?

Nope, you have gotten 2 years out of those tubes so be happy with that! I change tubes every year usually but I use EL84 amps
 
Re: Clean channel breaking up. Not in a good way.

This was my first tube amp and I purchased it used I think 2 years ago. I have not replaced any of the tubes yet. Mainly because even after researching it I'm not sure that I'm 100% on the signs of tubes needing replacement.

even if you are not sure 100%, its worth doing. If the old tubes are still good, then you have a spare set at gigs.
 
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Re: Clean channel breaking up. Not in a good way.

Clean the tube pins. If both channels use the same pre amp tubes, swap them over. See if the problem swaps channels. Then maybe get new tubes.
 
Re: Clean channel breaking up. Not in a good way.

Changed the power tubes. That problems all fixed. I'm now noticing a sudden drop in volume in the gain channel. It just kind of happens then comes back. -.-
 
Re: Clean channel breaking up. Not in a good way.

You may still have problems with the existing pre tubes.
As others have said...2 years of use...on a used amp...keep trying the tubes.:)
 
Re: Clean channel breaking up. Not in a good way.

Usually what will cause a clean amp to distort like you describe is power tubes, but it could easily be the preamps as well. Preamp tubes are where most of your tone comes from when power tubes will only enhance that when they become saturated(cranked!!)

If you have had it for two years and you have never replaced the tubes and the person you bought it from probably didn't either! So at this point you really don't know how old the tubes are. I would replace them all this way you will know whats good and what isn't. Tubes are not terribly expensive but most amp techs have a $75. to $100.00 minimum plus tubes. plan on investing $ 200 to $250 with a complete retube, cleaning & bias. It's money well spent your amp will be quieter and sound a whole lot better then it does now.
 
Re: Clean channel breaking up. Not in a good way.

Usually what will cause a clean amp to distort like you describe is power tubes, but it could easily be the preamps as well. Preamp tubes are where most of your tone comes from when power tubes will only enhance that when they become saturated(cranked!!)

If you have had it for two years and you have never replaced the tubes and the person you bought it from probably didn't either! So at this point you really don't know how old the tubes are. I would replace them all this way you will know whats good and what isn't. Tubes are not terribly expensive but most amp techs have a $75. to $100.00 minimum plus tubes. plan on investing $ 200 to $250 with a complete retube, cleaning & bias. It's money well spent your amp will be quieter and sound a whole lot better then it does now.


Nice thing about a Mesa amp with Mesa tubes I don't have to bias. And I honestly do not feel the urge to use different tubes. I like the sound it had for me before.

I was just planning on gettin some more pre tubes and replacing the set. But now it's just more time I have to wait since there is no one near me that stocks mesa tubes that I'm aware of.
 
Re: Clean channel breaking up. Not in a good way.

Mesa does not make tubes.
You do not need Mesa branded per amp tubes...only their rating of Power Tubes is a concern...and many tube dealers are hip to that.....I think.
At any rate...you can order whatever pre tubes you want to use...from anybody you choose.
best
 
Re: Clean channel breaking up. Not in a good way.

I also fully support changing the tubes , all of them. 2 years is a long time for power tubes, not so much for preamp tubes. The Preamp tubes do last longer as said.
For me I like to change my power tubes at least once a year and preamp tubes every year or so. Nothing sounds better then a fresh set of tubes. I strongly suggest sticking with the factory brand. This will avoid Bias adjustments every time you get new tubes.
You also need to at least check the Bias. If you don't know how, I suggest taking it into a authorized repair center and have it set properly.
 
Re: Clean channel breaking up. Not in a good way.

I also fully support changing the tubes , all of them. 2 years is a long time for power tubes, not so much for preamp tubes. The Preamp tubes do last longer as said.
For me I like to change my power tubes at least once a year and preamp tubes every year or so. Nothing sounds better then a fresh set of tubes. I strongly suggest sticking with the factory brand. This will avoid Bias adjustments every time you get new tubes.
You also need to at least check the Bias. If you don't know how, I suggest taking it into a authorized repair center and have it set properly.
 
Re: Clean channel breaking up. Not in a good way.

Mesa does not make tubes.
You do not need Mesa branded per amp tubes...only their rating of Power Tubes is a concern...and many tube dealers are hip to that.....I think.
At any rate...you can order whatever pre tubes you want to use...from anybody you choose.
best

No but they supposedly test and match them. Could be marketing hype but my mesa branded tubes have lasted appx 5 yrs and are just now needing to be replaced. Last couple yrs have just been playing at home but I was playing out regularly the first few and rehearsing with that amp. Maybe I got lucky. Still going with JJ for this retube as that's what my local shop keeps in stock. Easier to return if I have any problems.
 
Re: Clean channel breaking up. Not in a good way.

Finally was able to get all my tubes replaced. Still not working 100% for me. My input jack seems to be a little loose now. I'm hoping that's what's causing the problem I'm hearing now. I'm going to get to that when I've got more time. If not I've got no ideas.
 
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