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How do tube manufacturers like VAC get 55 watts per KT88 where others get only 30-35?

Just wondering how some push pull tube manufacturers like VAC and others get 55 watts per KT88 tube while others are more in the range of 35? Does driving a tube hard like this have any ramifications as to distortion, sound, headroom and tube life? I know VAC amps are highly musical so design, power supply and output transformers obviously contribute much to overall sonics. A company like Zesto gets about 25 watts per KT88 but uses a class A push pull circuit rather than class AB.  This seems like an attractive design.
I guess, as always, it's all in the implementation. Thank you for helping me to better understand.

normie57
bdp24's avatar
bdp24
4,908 posts
 
That’s nothin’! Roger Modjeski gets a hundred watts out of a pair of KT88’s in his Music Reference RM-200 MK.2, and without running the tubes hot. How? Creative, outside-the-box thinking. He discusses the amp's design in his now-dormant AudioCircle Forum.
normie57 OP
33 posts
 
Thanks bdp24. That's similar in that VAC gets 450 watts per Statement 450 Monoblocks with only 8 KT88s per side.
Like you say...implementation and out of the box thinking...and very special designers in Modjeski and Hayes!


mechans
2,999 posts
 

My Jadis DA-60 gets only 60 watts out of 4 KT -88s per side, in case your counting that's 15 per tube.  In  class A, push parallel  pull pairs, if I recall correctly. They could be understating the true output in addition you can use different output tubes in this amp.

I think the output transformers playing role in shaping the sound of most tube amps.

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