JADIS JA80 with 6550 or KT 88 or KT90 ?

from Jadis via email:
"JA30 is an autobias amplifier, it does not need any adjustment when you change tubes.
Kind regards,
JADIS Service Commercial / Sales Department
Chemin du Pech
11800 VILLEDUBERT. FRANCE
www.jadis-electronics.com
Tel : + (33) 4.68.78.63.30
Fax : + (33) 4.68.78.85.15"

The KT88's just arrived, replaced the KT90's with the Elecrto KT88's and after only 10 minutes of listening, promptly placed them back in their boxes. I'd say the quality lost is near 50%. In fact had the original JOR came with these 88's I'd be one very un-happy camper.
Dumb me, doubting the french.
loss in all three fq's in the 88's.
hopefully my seller will take them back with some discount of course,.if not I;'ll put them up for sale here.
Paul

Paul, whenever you retube an amplifier, this happens.

Put the tubes back in, and let them run in for at least 25 hours. They'll open up. Trust me. It's called break in.

Now, I'm not the biggest fan of EH KT88 or 6550, and you may end up preferring the Ei KT90. But, whatever you use when you retube, even if they're Ei KT90, when you first power them up, they're going to be EXTREMELY constricted sounding, especially at the frequency extremes, and lacking in power big time.

Personally, I like the JJ tubes the best. But, interestingly enough, I have also arrived at the conclusion that the Chinese tubes being produced today are far better than anyone would expect. I would have never believed this if someone told me, but I've tried some small signal tubes recently that surpassed some extremely well regarded NOS varieties. But, even they needed a day or two to open up to the point where I was satisfied with them. For my money, I'm hoping I never have to buy another Russian tube.

The 90's sounded excellent in the first minute.
Sound EXACTLY the same as today.
What I want to know is, does the other Jadis amps that use the 88 have simulairty as the EH88? If so then I may want to ignore the Cayin A88 and other Jadis' that use the 88.
Seems that most all Jadis uses 88's now.
Can the DA30 accept KT90's?

Thinking about it now, I made the best decision in getting the 88's trying them in the JOR. The 88 is not the sound I'm looking for. Its too mellow and vague.
I love the details, sharpness projected by the 90's. No I think I'll hold off buying the Cayin A88.
I think my next amp will be the JA30. I was thinking cayin 500, but there again its a big fat tube and will not likely present the striking sharp image the 90's produce.
Yep I think the DA30 will serve just fine...headed over one more time to Jadis' home page take a look at her.
Paul