Tube amp troubles.

[bjeans79]

I have a Peavey Classic 50 410. When I turn it up and play once its already warmed up some of the el84s glow red hot. I know tubes are supposed to glow, but this is definatly not right. And the longer I play on it the more I get this weird feedback sound like I have a wah pedal turned all the way high. Any ideas???

 

[tubeman87]

Re: Tube amp troubles.

Sounds like its time to replace the tubes, but then again I'm not an expert.

 

[SonofaMitch]

Re: Tube amp troubles.

there's deffinatly either a shot tube....or the Tubes are Biased wrong....most Likely the former of the 2 tho.

~Mitch~

 

[krankguitarist]

Re: Tube amp troubles.

Sounds like your tubes are goin to me. How long have you had those tubes in there for?

 

[ES350]

Re: Tube amp troubles.

redplating...bias or screen resistor is out of whack. Like a lot of the newer EL84 amps, these things probably have pretty high plate voltages. Take it to a tech, but you are probably going to need new tubes as well.

 

[marvar]

Re: Tube amp troubles.

redplating...bias or screen resistor is out of whack. Like a lot of the newer EL84 amps, these things probably have pretty high plate voltages. Take it to a tech, but you are probably going to need new tubes as well.

AGREED!
Get that amp to a tech, sounds like one of the above-

 

[Robert S.]

Re: Tube amp troubles.

Last time I had red hot tubes it was a screen resistor.

Good to see you here Mr. Jeans

 

[Dr.Mavashi]

Re: Tube amp troubles.

So should I check my tube by taking the metal cover of the pre amp and power amp tubes and turning the thing on to see if its red or blue .... I mean for the maintnace check of sorts ....

 

[Dr.Mavashi]

Re: Tube amp troubles.

so ???

 

[marvar]

Re: Tube amp troubles.

Unless you really know what you are doing/looking for, I strongly suggest you take the amp to a tech for some bench time.

 

[Rich_S]

Re: Tube amp troubles.

So should I check my tube by taking the metal cover of the pre amp and power amp tubes and turning the thing on to see if its red or blue .... I mean for the maintnace check of sorts ....

Redplating is only a concern with power amp tubes, and those don't have metal covers.