Power tube recommendation for Mark IV

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ClintN667

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I need to retube my Mark IV. What do you recommend for the power section?

I have several amps to work with now so I'm not on any huge hurry but I know I need at least a pair of 6l6's.
 
I really liked 6L6’s and KT77’s in mine. The 77’s contributed to the mids like an EL34, but they were tighter with bigger lows.
 
Being SimulClass, regardless of what tube you go with it's important to get the bias for each pair in the range that makes you happy. IOW you're not putting a matched quad in any Simul Boogie- for 6L6 and variants it needs to be a hotter pair for the A/B middle pair & a cold pair for the outer Class A slots. If you're doing EL34 in the Class A slots it can be a pretty normal pair. From there you can dial in what dissipation percentage you think sounds best. Personally I prefer around 60% for A/B and around 70% for A, but I can't be too picky because to change means buying more tubes in different ratings.
 
I dig the TADs 6l6’s. I got them in the 38 rating. I also dig the Tung Sol.
 
Can't beat Mesa STR-420 6L6s. They were designed around those.

GJgo is correct about bias—you'll want red or yellow code tubes in the outer sockets, and gray/green/blue in the middle.
 
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i see this question a lot, and ponder it myself, but the fact is, anything sounds good in those amps. they're biased cold, so really any 6l6 you throw in there isn't gunna be a problem, at least in my experience. i've used just about everything in mark amps over the years, since i've owned like 50 of them. I'll tell ya this though. when i had 3 strong, old, 70's tesla ecc83's in v1,2,and 3, and the small bottle tad 6l6's, that was probably the more "Stand out-ish" tone i can remember from the last 20 years of playing like 15 different mark IV's.
 
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