Amp Trouble

[DetroitBlues]

Ok, here's the skinny. I just brought home an used Peavey Valveking 112 50W tube amp. Tried it out yesterday for a long time, all the settings, different volumes, etc... Rocked the house with it. So today, brought in my Suprechamp XD and a Digitech RP500 to trade it all in. So now I went from a 15W hybrd amp to a 50W real deal. Awesome. Plugged it in today for a jam session. Crackle, snap, pop... WTF? Amp was perfectly fine yesterday, today its total crap???? I have a good friend looking at it hoping he can fix it. Problem is, I needed a good stage amp, the reviews were extremely positive everwhere I looked, so it was a no brainer. Changed cables, removed footswitch, wiggled the tubes, leaned it back, turned off the reverb tank, and nothing. Still crackling. Amp has three 12AX7's and two 6L6's. Not sure what to do. I hope our HOC botique amp builder can fix amps too! As Leslie Nelson once put it, "Just so you know, we're all counting on you!". But if anyone has ideas, let me know!!!

[Thundersteel]

Faulty tubes? Maybe you should swap them with known good tubes.

 

Perhaps some amp experts can give you further advice.

[Spectrum13]

Ok, here's the skinny. I just brought home an used Peavey Valveking 112 50W tube amp. Tried it out yesterday for a long time, all the settings, different volumes, etc... Rocked the house with it. So today, brought in my Suprechamp XD and a Digitech RP500 to trade it all in. So now I went from a 15W hybrd amp to a 50W real deal. Awesome. Plugged it in today for a jam session. Crackle, snap, pop... WTF? Amp was perfectly fine yesterday, today its total crap???? I have a good friend looking at it hoping he can fix it. Problem is, I needed a good stage amp, the reviews were extremely positive everwhere I looked, so it was a no brainer. Changed cables, removed footswitch, wiggled the tubes, leaned it back, turned off the reverb tank, and nothing. Still crackling. Amp has three 12AX7's and two 6L6's. Not sure what to do. I hope our HOC botique amp builder can fix amps too! As Leslie Nelson once put it, "Just so you know, we're all counting on you!". But if anyone has ideas, let me know!!!

 

Have you checked... the fuse and/or the speaker connecting wires?

[kbp810]

She's all better - looks like it was just a bad 12ax7 in the PI

 

Being late and surrounded by nearby neighbors, I'll wait until tomorrow and crank it a bit more to confirm, but I let it warm up for about 10 minutes, hit a few chords and it was sounding just fine

 

I'm not sure if the stuff I've schlepped together quite qualifies as "boutique" though

[DetroitBlues]

She's all better - looks like it was just a bad 12ax7 in the PI

 

Being late and surrounded by nearby neighbors, I'll wait until tomorrow and crank it a bit more to confirm, but I let it warm up for about 10 minutes, hit a few chords and it was sounding just fine

 

I'm not sure if the stuff I've schlepped together quite qualifies as "boutique" though

 

Dude! You're my hero!!!! I hope that's all it was. Trust me, after your champ build project, you are the real deal boutique amp builder now! I'll still bring the extension cab you made me since I cannot use it now. Since you have it all weekend, can you check to see if the footswitch keeps killing the volume? Thanks a million! I'll have to make you another cigar box guitar!

[GuitArtMan]

She's all better - looks like it was just a bad 12ax7 in the PI

 

Being late and surrounded by nearby neighbors, I'll wait until tomorrow and crank it a bit more to confirm, but I let it warm up for about 10 minutes, hit a few chords and it was sounding just fine

 

I'm not sure if the stuff I've schlepped together quite qualifies as "boutique" though

Man I had a phase inverter go intermittent on me - actually just oxidation in the tube socket. My amp started making all these weird flying saucer noises, on top of just generally sounding weak and thin and wimpy. Glad you got it worked out.

[kbp810]

Well, the story doesn't end there after all...

 

Cranked it up and was playing it for quite a while, sounded great and working just fine

 

Took a break, headed out to run a few errands, came back and decided to turn it on again, played for a few minutes and the problem came back again - and it only happens intermittently on low notes, playing highs consistently ring through loud and clear

 

Being that it was just bought yesterday, I'm not sure if you really want me to dive much deeper into it - hate to say it, but might be best to take this one back and seek out another

[yoslate]

Well, the story doesn't end there after all...

 

Cranked it up and was playing it for quite a while, sounded great and working just fine

 

Took a break, headed out to run a few errands, came back and decided to turn it on again, played for a few minutes and the problem came back again - and it only happens intermittently on low notes, playing highs consistently ring through loud and clear

 

Being that it was just bought yesterday, I'm not sure if you really want me to dive much deeper into it - hate to say it, but might be best to take this one back and seek out another

 

 

kp, have you checked the biasing?

[kbp810]

kp, have you checked the biasing?

Yep, both 6l6's had a draw right around 33ma

 

But must admit I almost didn't want to check it... the retaining rings they put around their power tube sockets have sharp little claws on them, and not very much give - it was a total PITA just pulling the tubes out, and when I was done I thought I was just about never going to get my bias rig back out of them

[DetroitBlues]

So I'm going to return the amp, thanks so much KBP for helping me. I'm going to return the amp in the hopes I'll walk away with a new verison of the amp, even if its their floor demo model....