Intermittent Tube Heater Problem

[Toneseeker]

A friend came to my house on Sunday with his 80's Fender Concert.
He complained about it being distorted and generally weak sounding on the clean channel. I plugged in my telecaster and tried both channels and they both sounded horrible. A quick look at the 6L6 tubes (Svetlana winged C) which were fairly new revealed that one of them wasn't glowing. I reseated it and it started to function. Shortly afterwards it stopped again. I switched the tube positions and the fault followed the tube. OK faulty tube.. The thing is, I have another tube which came as stock in a Hot Rod Deluxe (Groove tubes) which does exactly the same thing. A bit of a coincidence maybe but I wondered if it was more common. Is it internal problem with the tube or external pins?

[steve25]

Its probibly a combination of pins 2 and 6 in the socket needing to be cleaned and retensioned and those same pins on that output tube being messed up from the arcing of the intermitant connection.
Also note that if the amp has ever had JJ brand output tubes in it that there pin heads have little to no taper and in most amps will streach out the socket pins and make of a poor connection when other brand tubes are used.

[Toneseeker]

Thanks Steve,

I didn't think to try cleaning the pins and retensioning the socket. That's a handy tip about the JJ's. Maybe I can get my buddy to do that before he orders another pair of tubes.

[limbe]

If the problem persists,change the sockets.You don´t want the amp going down during a gig.Hope it works out for you!Oxide is a nightmare