JADIS JA80 with 6550 or KT 88 or KT90 ?

Thanks to all of you for your contribution.

This is to let you know that I have purchased the SVETLANA KT 88 and I that the sound of my Jadis JA80 improved a lot.
These valves are much better than the 6550 or the KT90.
Sound became much more airy and halographic; extremes much more natural , without loosing detailed.
I can assure that this was one of my best investments to improve my sound.

Regards specially to Khrys

Joao

The kt88 definatly my favorarate is the 6ca7 for musicalty and close second is the 88 none of the midrange glare the 6650 or KT90 has, the 88 is just more full bodied much more texture smoother highs and more natural, have had several pairs of JA80S also have JA200S JA500S JA50 AND 100s I like the 80s and 200s the best.

Interesting. Do you guys think if I switch the KT90's for 88's that my JOR will sound even better. The 88's have been recommended, but I didn't feel the need.
Also which 88's are good value. I don't want to spend say more than $200.
Paul
Baton Rouge

Of the 6550s I used in my old JA80s (from around 1993, had them over 10 years), the best of current production tubes were true Svetlanas (not Sovteks). They had some of the midrange of the better KT88s, though could not match them in that area, and had the best bass control of all the tube types I used in the 80s. They will give you most of what these amps can offer. The best 6550s ever in my amps were the Tung Sols, but you have to make sure you get the real ones, as there were a lot of phony ones out there in the market. And the best tubes I ever had in my JA 80s were NOS MO Valve KT88s (GEC Gold Lions, etc.). They are pricy, but lasted four times longer than any 6550 type tubes in those amps, had the midrange of EL34s (which sounded great in that area while they lasted) but much better bass, and seemed to be just the perfect tube for those amps. I did not like the KT90s in my amps--felt they were cold and lifeless, became stale-sounding after a while. Anyway, I see you got some Svetlanas, so you've gone the right direction, in my view.

Bartokfan: As Khrys pointed out above, the JOR's transformers are supposedly optimized for the KT90 tubes, though there still are many who prefer EL34s and KT88s in the amp. KT88s will likely give you a lusher midrange and a more "tubey" sound than the KT90s, which are leaner (Khrys's description as the perfect transistor is the way I felt about the KT90s too). As far as current production recommendations, I don't have any, but check the archives, there are a lot of recommendations on current production KT88s.