master compatible tube list

[stephen sawall]

Another option would be to use a pair of 6L6GC's in the inside sockets along with a pair of the KT66's in the outside sockets. This setup will get you a more aggressive mid range while still retainign a very deep and tight low end. This would add 38.00 to the "6L6GC" quote below.
JJ Electronic now has a great new production 5U4GB with dynamics equal to the old RCA 5U4GB, not too stiff with just the right amount of sag. These are a very nice upgrade from the stock 5U4.

So this option should be safe to do for the Mark V? if so, it looks very attractive to me. Especially with the High gain Ecc83s

PS. Awesome Thread!

I had a quad of KT66 in my IV for almost a year ..... the cleans and leads were huge. Much bigger sound than 6L6. When doing rhythm sounds it the sound was much looser. The bass was just not near as tight. That was a few years ago and vintage KT66.