How to mod bias in my simulclass Mark III

[Reeko81]

Hi! I'm tired to buy only mesa tubes, and want to experiment with different tubes...I know i'll save some $$ too and can achieve also good tones!
Since my amp is a simulclass, is it possible to make a mod with an adjustable bias, allowing me to continue playing with both El34 on outer positions and 6L6 on inner positions?

 

[eldi]

Correct me if I'm wrong, but I believe that Groove Tubes that are numbered 4, 5, & 6 are within Mesa'a voltage specs. Also, if you order tubes from Eurotubes (http://www.eurotubes.com/), and tell them its for a Boggie, they can ship you tubes that are within the correct voltage specs as well. These are better alternatives to having your amp modded for adjustable bias &/or exclusively using Mesa branded tubes.

 

[6L6C]

I looked into to this with my Mark IV I’m also running the (2) 6l6’s and (2) EL34’s and I also talked to someone who did it to his Mark IV. Long story short at least with the IV, it is a bit of a balancing act because of the simul-class and all the different modes of operation (tweed and full power with the IV). However you can come allot closer! As eldi said

Correct me if I'm wrong, but I believe that Groove Tubes that are numbered 4, 5, & 6 are within Mesa'a voltage specs. Also, if you order tubes from Eurotubes (http://www.eurotubes.com/), and tell them its for a Boggie, they can ship you tubes that are within the correct voltage specs as well. These are better alternatives to having your amp modded for adjustable bias &/or exclusively using Mesa branded tubes.

And he is right! But if you want to get into NOS tubes having a fixed bias really is not going to cut it. I have not done it yet myself I think I would like too. My 6l6’s are running a little cold but my 34’s are extremely cold. But I do get a great sound. I use Mesa tubes BTW. But I would like to enter the world of NOS.