Power Tubes for Mk IIb...KT66?

[Murfman]

Can you substitute KT66 for 6L6 tubes in a mark IIb boogie amp? Has anyone done this? I need to get some new tubes and am looking for something a bit different.

-Murf

 

[gonzo]

the 2b is biased for 6l6's....

 

[Boogiebabies]

I run them in my Dual Rectifier. At 460V to the plate and -51V of bias they draw 35mA, which to me is perfect.
They cannot for any reason be used in an outer simul-class socket !!! I use the GT version with a #5 rating so if you
have a 60/100W, they should be fine as the IIB bias is set to -52V and the plate voltage is very similar.

 

[Murfman]

Very cool. I can't wait to try them out. I found a set of the '5' rated GTs online. I'll post my results after I give them a test drive.

-Murf

 

[gonzo]

another idea for 'something different'...

is another tube set i have for my Mark2b:

Groovetubes Substitube, with EL84.

change the boogie to a hyper drive AC30

 

[Murfman]

Gonzo...I have a pair of the 928-pr Groove Tubes Substitubes. Groove Tubes has stopped making these. I just bought another pair yesterday so I can run 4 at once...(Yeah Vox AC30!)

Anyway, I would suggest anyone that has been considering these to get them asap as once they're gone they're gone.

I got mine from South Valley Vintage Amps in Morgan Hill California. He has one duet and 4 quads left. He told me he got the last there was from Groove Tubes.

I spent an hour on the internet trying to find these and finally found a pair with him.

-Murf

 

[gonzo]

INTERESTING.

wonder why they quit making them....?

just lack of demand?

i think they work really well.

and WAY WAY cheaper than doing permanent MODS, and actually works better to my ears, than re-biasing and re-tubing amps that were never designed for those sounds to begin with.


thanks for the headsup on that.
i've got the one pair, i'll keep a look out for another.......