Power tube issue?

[sbrett]

So I was jamming a bit on my lunch hour when all of a sudden I notice a fairly loud hum, very low frequency. Unplugging the guitar didn't remove it, turning down the master volume didn't remove it (assumed power tube issue), and then I noticed a bit of a 'burning' smell. There's a mirror behind my Mark V and I noticed that the second power tube from the left (as you're looking at the back) is glowing MUCH brighter than the others. I immediately shut down the amp.

Now I'm assuming since a fuse didn't blow that I shut the amp off in time to avoid major damage (the manual seems to indicate this also)...do you think just replacing the tubes would be fine, or is there a chance something got fried? I've had it since March. Probably has at minimum 300 hours on it.

And while I'm on it, how bout throwing some EL34s in there? What kind of life are you guys getting out of your EL34 equipped Vs?

 

[boogieman60]

Happened to me the first time I plugged mine in. You fried a screen resistor because of a bad power tube. Did you get smoke? If you did it's a sure thing. Take it to a Mesa approved sevice center...Free fix...

 

[boogieman60]

You might try to change the position of the power tube in question. If you put another tube in the socket that was glowing and it's ok ,it's the tube, and the tube that was bad will still glow no matter where you put it. However if that socket always glows no matter what tube you put in it, it's the amp. (screen resistor.) Hope that helps.