Weird sounds

[HamerDave]

Can anyone give me an idea what a damaged output transformer in a tube amp might sound like? I have an amp that had a hard output tube failure. The main fuse blew but, after replacing everything, the amp has a weird breakup. It's not musical at all. It happens at any volume level. It's like the signal builds up to a certain level then something is overloaded and just loses control. A sweet note that builds up then turns to a tone fart past a certain threshold. I've tested the caps, all good, none of the tone controls seem to effect the issue. Neither do the gain or volume controls. It happens at any volume level from whisper to rage. I'm totally flummoxed 😶. Help please.  

[Jakeboy]

I have had one amp in my life that ate OTs....each time, the output, the volume would simply get quieter and quieter....gradually.

[tbonesullivan]

What did you replace besides the fuses and tubes? When power tubes go they can take other things with them.

[Jeff R]

I had a power tube fail and take out a screen grid resistor or something like that on my Boogie Mark V earlier this year. Belch of smoke (and fried electronics stink) and amp dead. I thought it was funny a little black Tylenol capsule-sized doodad that cost about two bucks on MB's repair details sheet could wipe that loud, mighty and heavy box down for the count.

[HamerDave]

Aaaaaaand we have a winner!  Jeff R with his anecdote got me thinking about the wave form and how the signal builds as it passes through each stage.  Since the sound I was getting was like a really ugly fuzz. So I checked the screen resistors on each stage. V1 and V2 were both shorted through. The both measured basically 0 ohms.  Short story long, I swapped them out, upgrading to top quality ($4.95 for the pair. 😜) and we have beautiful music again.