Help identify this tube problem.

[ArtieToo]

Update at post #17.

Hey all. My experience in tube amp troubleshooting is sparse. I just fired up my Traynor YCV20WR and it has a strange sound. Imagine dropping a quarter in a Mason jar, and setting it on a speaker that's playing loud. Is this something a tube would do when it's going bad?

Thanks;
Artie

The tubes seem to be seated well and are held in with hefty tube retainers.

[Jeffblue]

Hi Artie. Is it a preamp or power tube? Have you tried tapping each tube while the tubes are warmed up with a pencil or chop stick? That might give some kind of clue which tube is going bad or microphonic.

[JMP/HBE]

Bad tube / thread.

[80's_Thrash_Metal]

Yes, turn it on and make sure the speakers get volume.
tap lightly with something wooden on each tube.

Sounds like one of them has gone microphonic, or is ready to die, to me.
probably a pre amp tube, probably #1 or #2
But that's just my guess.

[ArtieToo]

Thanks guys. I'll do the tap test 1st thing tomorrow. There appear to be only 3 tubes. I'm thinking one preamp, and two output, in a push-pull mode. I'll report back tomorrow.

[ArtieToo]

I couldn't wait. I see what's going on now. The three tubes I can see are the splitter and 6BQ5 push-pull tubes. The two 12AX7 preamp tubes are mounted horizontally inside the chassis. I'll have to take this thing apart to get to them. Tapping on the splitter and outputs did nothing. So it's either the preamp tubes or the voice coil.

Film@11.

[El Dunco]

Have a look at the tubes when it does that and I’m pretty sure it will reveal itself. If not, grab a pencil and give each one a little tap.

[ArtieToo]

Have a look at the tubes when it does that and I’m pretty sure it will reveal itself. If not, grab a pencil and give each one a little tap.

Yeah, I did with a wooden spoon. No affect. The preamp tubes are hidden behind a metal plate that needs a Craftsman torque wrench to loosen. I'll work on it tomorrow.

[El Dunco]

Yeah, I did with a wooden spoon. No affect. The preamp tubes are hidden behind a metal plate that needs a Craftsman torque wrench to loosen. I'll work on it tomorrow.

A wrench? Boy they’re really in there good. All of mine just have thin, bayonet mounted covers that I keep losing. Any time I had a lawnmower sputtering sound, I could see the culprit tube flashing away.

[ArtieToo]

A wrench?

Traynor did this right. This chassis is way more robust than my Honda. Or my Silverado, for that matter.

[El Dunco]

Traynor did this right. This chassis is way more robust than my Honda. Or my Silverado, for that matter.

Looks like it was built for the gigging musician expecting small-arms fire.

[ArtieToo]

Looks like it was built for the gigging musician expecting small-arms fire.

I'm fixin' this tomorrow. We have the technology.

[El Dunco]

I'm fixin' this tomorrow. We have the technology.

Right on. If you can’t do it, no-one can. I still refer back to your pickup mods to this day.

[ArtieToo]

If you can't do it, no-one can.

Not exactly. I have a "tube-amp" guy. We each cover our own area. (For each other.)

[GuitarDoc]

To me it sounds like it's probably a preamp tube going microphonic. Hope you got that bullet-proof cover off and did the wood stick tap test. If you can't see one tube glowing redder than the other, the tap test should reveal the microphonic culprit.

Did you get this straightened out?