Squealing Amp (F30)

[NDRU]

Yesterday my F30 started squealing. Kind of like feedback, but I also heard the bang of the reverb tank sound as if I'd set the amp down hard, and it sounded kind of like interference--like a power drill going nearby.

I was playing on the clean channel, no gain. The squealing continued on both channels

I tested the tubes, they all seemed fine as far as I could tell. The problem also had stopped after I turned it off for a while.

 

[JW123]

My little Subway Rocket is in the shop for the same problem. I havent heard what was wrong yet.

 

[NDRU]

the worst part is it's not doing it now!! :x

 

[bgroup]

With my F50 it was tubes...

 

[Lou]

Ned Beatty wishes he could take back that squealin' from early in his career

 

[Alivefor5]

Ned Beatty wishes he could take back that squealin' from early in his career

Bwaahaha !! Unforgetable scene.

 

[NDRU]

With my F50 it was tubes...

preamp or power?

 

[Lou]

Ned Beatty wishes he could take back that squealin' from early in his career

Bwaahaha !! Unforgetable scene.

 

[dodger916]

With my F50 it was tubes...

preamp or power?

It's probably a preamp tube. I've had some NOS preamp tubes did that.

 

[NDRU]

Tested the tubes again. Seems that #2 was maybe possibly microphonic. It made a slight noise when I tapped it at high volume.

But I won't know until I use the amp again. It bugs me because the problem wasn't constant, but more of a one time thing.

Nothing like an amp you don't trust! :roll:

 

[JW123]

My Subway was a preamp tube. If you have spares just change the one that you tapped out.

Good Luck