Sound of SED Winged C KT88 vs. SED Winged C 6550's

Well Kevin may not have heard a difference, but if he is honest about it then he needs to tune up his ears and/or his equipment. I think he is just 'position' adverse and as a sealesman he doesn't want to jeopardize any potential sales.

In my experience, and just for the fun of it I have to mention that this was formed from using Primaluna amps (as well as four other ones) the SED KT88 is a bit 'full' in the upper bass and the upper-mid range is a bit elevated. Gives them a little of the sense of sparkle. The SED 6550 is much more linear throughout the FR. Tight, non-bloated bass, smooth midrange, and slightly rolled highs.

FWIW, I happen to like the SED KT88's in the PL5, but not anything else I own, when I compine it with the PL3 pre-amp. I prefer the SED 6550 compared to the SED KT88 in my other amps. Actually I've started to grow fond of the re-issue Tung-sols. But they take forever to break-in! :-)_

Newbee - just for clarification, I never got thru to Kevin Deal, as one of his helpers would not let me talk to him... so it was one of Kevin's employees that said there was no sonic differences between the two tubes.

Thanks for the useful info... the sparkle of the SED KT88 is what I'd like to move away from.

Newbee, can you comment on the sonic differences between a SED 6550 and Reissued Tung-Sol 6550? ... which one has less smear when dealing with complex passages and poorly recorded compress music.

Thanks!

Bit out of topic.

I never tried SED valves, but in my PL Plologue Two, KT88 gives more body, like Newbee wrote, and I think this is what you may expect, generally speaking.
Personally, I compared NOS 6550 Tung Sols grey plates with holes, NOS 6550 Tung Sols Black smooth plates, NOS 6550 Sylvania and NOS GEC KT88, which I am using now. NOS 6550 Tung Sols Black smooth plated are great, but not as much as KT88, however may depend in which amp, or simply putted set up, you are using them.
The bad thing, as always with NOS, they are very expensive, but from what I heard/read, TungSols, even they are below their minimum, still sound wonderfull, talking about Black smooth plated from 50's, but they dont have that magic of GEC, I would say KT88 are more involving/musical as well, at least to my ears.

Getting information out of Upscale Audio isn't as easy as it used to be.

There are some major differences between a KT88 and a 6550 and I have always heard a big difference.

I recommend you try Roger Modjeski at Ram Labs for tubes. It's a much better experience.