Tubes gone bad

[pbman1953]

I'm trying to help a friend-


Fender Super Champ x2-   amp with 1-12ax7 and 2 - 6v6- all JJ's




While playing he noticed no power and distortion- The amp is 5-6 years but with light use and the amp was biased.


The 12ax7 was fine but the power tubes were cooked. Shouldn't they last longer? Plus, I know it would be hard, but any idea what would cause them to go.




Any tube suggestions?


Thanks

[shooter]

but any idea what would cause them to go.

typically current, either because of a fail in bias, B+, OT circuit.

Pull tubes, verify VDC, connections out to speaker, verify bias without tubes.  IoW, eliminate the good stuff n the problem is left 

[pbman1953]

Thanks, I'll tell him to have the amp looked at

[bmccowan]

First thoughts when I saw

Tubes gone bad

Hangin' around with the wrong crowd (transistors); smoking; squealing; etc.

[shooter]

Hangin' around with the wrong crowd (transistors); smoking; squealing; etc.

 
sound like the '90s kids that lived around here 

[bmccowan]

Hey you tubes - get off my lawn!

[shooter]

Hey you tubes - get off my lawn!

there were still signs in Norfolk VA when I was a sailor "dogs and sailors stay OFF lawn".  we all wizzed on the signs