Need advice on a tube amp repair.

[Artie]

Hey all. My friend just scored a killer deal on a Traynor YCV20 amp. This was actually the personal amp of the music store owner, whom I've been doing business with for several years. Anyway, the thing looks like new and sounds killer, but it does have one little problem. It has that subtle sound of a screw rattling in a mason jar deep within it. It uses two 6BQ5's, and three 12AX7A's. Is this more than likely the sound of needing new tubes? Preamp tubes or power tubes, or both? Or neither?

Thanks all;
Artie

 

[Nostalgic Distortion]

Re: Need advice on a tube amp repair.

I've heard something similar to that when a big bottle EL34 went micro phonic. It's probably a valve issue but I'd have a tech have a look before dropping the cash just in case.... I hope it is just a tube, that's an awesome amp!!!

 

[PFDarkside]

Re: Need advice on a tube amp repair.

Dumb question, are you sure there isn't a screw rattling around inside the chassis?

 

[Funkfingers]

Re: Need advice on a tube amp repair.

+1

Check the loudspeaker fastening bolts.

Try each of the 12AX7 trio as V1. Does this change how much of the unwanted noise you can hear?

Might not be valves at all. Could be electrolytics.

 

[Artie]

Re: Need advice on a tube amp repair.

Dumb question, are you sure there isn't a screw rattling around inside the chassis?

Not really a dumb question. I'm pretty sure that's not it, because it changes with the volume.

+1

Check the loudspeaker fastening bolts.

I did try to "wiggle" it. It seemed solid as a rock.

Try each of the 12AX7 trio as V1. Does this change how much of the unwanted noise you can hear?

Might not be valves at all. Could be electrolytics.

Thanks Funk. I'll give that a try. I'll also see if I can record a short clip.

 

[TwilightOdyssey]

Re: Need advice on a tube amp repair.

With the amp on, try tapping each valve with a pencil eraser. Microphonic valve will show itself pretty readily when provoked.

 

[Artie]

Re: Need advice on a tube amp repair.

Cool idea. Thanks TO.

 

[GuitarDoc]

Re: Need advice on a tube amp repair.

Probably a preamp tube. Do the tap test as suggested.

 

[Kamanda~SD]

Re: Need advice on a tube amp repair.

How ****ing long does it take to tap tubes?

Seriously though, do that first. However, if it hasn't been serviced in awhile its always good to have it looked over by someone, check all the caps etc too. Totally worth it with any newly acquired amp imo.