Amp Problem

[bubs_42]

Ok, I've been having a loss of high end in my amp and some overall dullness. So I figured it was time to swap tubes, so while I was waiting for the set to arrive, I started to have some distortion no matter what channel on the trail off of a chord or note. I jetted up to the local shop, picked me up a set of 6v6's, installed them, biased the amp, and everything we pretty glorious for about 15 minutes. Then a dramatic loss of power, not so much distortion or dying sound but the amp went from club level to bedroom. So just to be sure I bought new 12ax7's so I could swap them out and around. This did not solve my issue, could it be that the new set I bought just shot craps that fast? Or something else, i've check speaker wire, swapped guitars, swapped cable, OD channel is weaker than the clean channel. Beyond swapping tubes and Bias the amp that is about the extend I go. Wish I had a tube 

 

Just thought of this, if I pull the chassis and one of the tubes are bad will it not be bias properly?

[HoboMan]

I had something similar happen with my Budda SuperDrive a few weeks ago.

Take off the back of the amp so that you have good visual access to the tubes. Turn on the amp and play thru it and watch the tubes. Look for any obvious redplating.

If nothing shows up right away leave the guitar plugged in and the amp running. Check the tubes every few minutes.

On mine one power tube showed bad immediately. Took about 10 minutes for the second tube to start redplating.

[bubs_42]

That is what the first set of tubes did. 

[HoboMan]

What about the new set? 

The tubes I put in mine were new and they still redplated. I have since put in another new set and have had non issues.

[triodecr]

What amp model?

 

[HoboMan]

If it's a Splawn, Scott has great support and will usually talk to you on the phone.

[bubs_42]

Nope my Splawn did not stick around very long. Just wasn't my thing. Its my Fuchs 2 and when I get a minute (Probably Friday) I'll check it out again. I did however find out what was causing that damn harmonic ring. Its the V3 retainer baseplate. A little tweak and that stopped when I tapped on it.  

[bubs_42]

Took the MKII to a different repair guy in town, one day turn around and it turned out the Preamp Section took so much heat during the meltdown it needed the soldering touched up and tubes replaced. The ringing I was hearing was a precursor of what was to come.