Fender/Groove Tubes biasing

[Guitar Guy]

I have a question about the color coded fender/groove tubes. I have them in a fender hot rod amp and i haven't changed the tubes. I think it is about time to do so and i read in the manual that if you replace them with the same color coded tubes, that you don't have to rebias them. But i also read in another book that you should always rebias after a tube change or risk damage to the amp. Do i need to rebias if i replace them with the same color of tubes?

 

[Gearjoneser]

Re: Fender/Groove Tubes biasing

I can't seem to remember if the Hot Rods had a bias pot. Sometimes, on their tubes, you can still see the original labeling from Sovtek or Svetlana. When looking at the Fender GT tubes, look closely and get the ones with a burnt orange base...the Svetlanas. Then, just pop them in.

Most of the popular tubes like Svetlana, JJ, Sovtek all fall into a normal bias on Fenders, so you may even be able to save money and just buy JJ's or Svetlanas.

The only thing you never want to see is the plates inside the tubes turning orange or red. Or, having your amp sound weak or grainy. If that happens, get it biased. If not, it's probably fine, and operating in a safe range.

 

[kmcguitars]

Re: Fender/Groove Tubes biasing

Hot Rod Deluge's DO have a trim pot for bias adjustment. Even better... they have a bias probe check point on the PCB. All you need is a DDM, pair of alligator clips and some common sense (i.e.) Understand that you are working with high/lethal voltage and it's easy to bias a HRD. J. Holten and Bob from eurotubes both have tutorials on how to bias a HRD on their sites.

BTW, I wouldn't put the same Groove tubes in a HRD. You can get better tubes cheaper. Talk to www.dougstubes.com

 

[Bezmotivnik]

Re: Fender/Groove Tubes biasing

I wouldn't put the same Groove tubes in a HRD. You can get better tubes cheaper.

Agreed, from almost anyone who benchtests and culls raw stock. Triode, Lord Valve, Eurotubes...

 

[Guitar Guy]

Re: Fender/Groove Tubes biasing

What types of tubes should i get then? I'm assuming that i should get it rebiased as well if that is the case.

 

[drew_half_empty]

Re: Fender/Groove Tubes biasing

always rebias

groove tubes makes a lot of claims that are... weird

then again bob has strong financial ties to the JJ company

but yeah i'd go with different tubes. What kinda tones you going for? any frequency you wish you had more or less of? warmer? brighter?

 

[Guitar Guy]

Re: Fender/Groove Tubes biasing

always rebias

groove tubes makes a lot of claims that are... weird

then again bob has strong financial ties to the JJ company

but yeah i'd go with different tubes. What kinda tones you going for? any frequency you wish you had more or less of? warmer? brighter?

what type of 6l6 and 12ax7 should i get then for a good CLEAN classic rock type sound as a used pedals for most of my distortion?