6550 vs KT88 vs KT90

Rcprince, you may want to e-mail Jadis regarding the use of KT90 tubes in your amp. They go out of their way to recommend KT90, and to avoid KT88 with me. They say they have seen reliability problems with KT88s. I have never had this experience. Quite the contrary. And, while Frank Garbie is very helpful, his information is often at odds with what I get from Jadis directly. So, again, I would ask THEM about KT90s in your amp. They always give me a response within a day or two. Good luck!

Trelja: Thanks, I'll give that a try. On the reliability, the newer KT88s, particularly the Chinese lower grade makes, have had reliability problems. The vintage stuff is a different story. All the 6550s I've used in the JA80s have started going bad, and blowing the protective fuses, within a year to 14 months (in my ARC Classic 150s, the same Phillips tubes lasted 5 years). I've had the KT88s in there for over two years now with no problems. I must admit having a preference for the MO Valve KT88s, even over the KT90s I've heard in Jadis equipment; just a matter of preferring the darker sound, I guess. But the prices.....

Trelja,which of the Rogue products have you used.Can you comment on svetlana 6550C Vs Sovtek Kt-88

Tml12, I have EXTENSIVELY used both the stereo and monoblock Rogue amplifiers. Wonderful sound, but not what I call "classic tube" sound. The new tube sound(Rogue, Jadis, Audio Research) is much more neutral, powerful, and extended(solid state sounding, at least to me). What people mean when they say the best of ss and tube amps are converging. The amps sounded more to MY liking with the KT88s. A bit more sweet. But then, I like syrupy sweet tube amps(even though my Jadis is not). I know you will say this is crazy, but I always preferred the Jolida 302B over all the other Jolida integrateds, and the Rogue power amps. But, that goes back to my sweet sounding tube preference. In reality, the Rogues offer MUCH more: power, neutrality, bass AND treble extension, etc. All of the things that "the absolute sound" is supposed to sound like. Just trying to be honest in regards to my bias.

Thanks trlja