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Re: Genelex GL KT77s don't have pin dia issues...

...Alex is asking about the real thing not JJ's repro. Mechanically the Genelex will work just fine.

The real question here is whether they'll work OK electrically and sonically in Alex's equipment. The KT77 is a beam tetrode (similar to GE 6CA7) compared to the EL34 which is a "true" penthode. Each has it's own sound and what one prefers is personal. Although there is a mystique assoc with the real KT77, my experience is that it is totally unwarranted. It's a decent sounding tube in the equipmwnt I've heard them in but not worth the price. I think they sound very much like the much less expensive US mfg beam tetrode 6CA7s.

The other issue to watch out for here is equipment compatibility. I remember years ago reading a Stereophile review of some tirode strapped Airtight amp where the smug reviewer (Tom Gillet IIRC) subbed a quad of GL KT77s for the EL34s it came with. The amp could only make about 1/3 of rated power. Couldn't figure it out for the longest time. He put the EL34s back in and all was well. Lesson: Tube rolling doesn't always work out as planned.

If I was Alex I'd try the GL KT77s but I'd also be prepared to flip'em quick if they don't work out. I might also be inclined to try the GE or Sylvania/Phillips 6CA7s too...but hurry, guitar players love these things and burn them up quick.


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  • Re: Genelex GL KT77s don't have pin dia issues... - Steve O 19:51:48 02/22/07 (1)


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