2. amps-preamps
  3. 1204686714

Triode versus Ultralinear/Pentode

Does triode always sound better than ultralinear/pentode in circuits and parts of similar quality? I'm not really interested in SETs, but triode wiring of EL34/6550 etc. I have a CAT JL2 wired which has 6550s connected in triode and is the best amp I have ever heard in my system. I also have a Music Reference RM9 MKII with EL34s connected in ultralinear and am considering having them rewired for triode operation as I assume that is one of the reasons the CAT sound so good (those transformers may also have something to do with it). Thanks.
pubul57
tvad
9,467 posts
 

03-09-08: David12
Taking up atmasphere's point and changing the question. Is it always true that the compromises envolved in making an amp adjustable between Triode and Pentode, mean they will perform worse than an amp optimised for triode or pentode only?

I owned a VAC Phi 110/110 that had both modes. There was no compromise in performance that I could discern from other amps I have owned that were pentode only. In fact, when run in triode with zero negative feedback, in many respects it was the best sounding amp I've ever owned.
pubul57 OP
3,712 posts
 
I thought that Atmasphere's point was that "switchability" is often a compromise, but not necessarily so and not always - but one should tread carefully.
atmasphere's avatar
atmasphere
7,068 posts
 
Pubul57 is correct. Some amplifiers pull it off quite well- others don't. I rebuilt a Marantz 9 from years ago- the amp sounded OK on Pentode, but really, triode mode was the really useful mode if you were listening seriously. Most triode amps today would eat if for breakfast, though. Its a fact that pentodes wired in triode do not have the same linearity of real triodes.
More to discover