Which KT88s for Cary SLI-80?


I'm shopping to replace the output tubes to my Cary SLI-80 and have been recommended several new production KT88 tubes--JJ Tesla, Groove Tube, and the Electro-Harmonix EH tubes. I notice Cary has the Electro-Harmonix tubes in their F1 premium model. I've been using Svetlana "C" KT88s with good results, but I want to warm the midrange and sweeten the top end. I play mostly classical music--Renaissance choral, Romantic Italian opera, and symphonic orchestral music. There are complex and massed trebles in these all the time that make for difficulties. For example, I tried using Siemens/RFT EL34 tubes, which created much more air and spaciousness, but they also seemed to lack enough power to negotiate these complex massed treble passages--choral voices, unison violins, etc. The system presented an edgy glassiness at the top that masked all other details at dynamic peaks. This doesn't occur with the Svetlana KT88s, which also have more focus, but I'd prefer more warmth, body, and air in the music if possible. My other tubes are Mullard CV378 rectifiers, Brimar 6SN7s, and Mullard E188CC/7308s. I use Audience Au24 ICs and speaker wire, an CAL CL-15 player, and Sonus Faber Grand Piano Home speakers. Suggestions? Characteristics?
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I have a quad of Penta Labs KT88SC with the three oval holes, which I'd sell at a nice discount if anyone is interested in them. It's not worth it to me to purchase an ad. I'm only semi-motivated to sell them. They sound excellent.
I use the JJ Tesla KT88 and like them a lot. I would suggest trying the EH KT88. I have not tried them, but all the other EH tubes I've tried (12AX7, 6922) have been over-achievers. The 6922 gold pin was better than my Siemens NOS tubes that they replaced. The JJ's are excellent all around, but I think they are more dynamic and fast than warm, which is what you're looking for. The EH KT88's are much less expensive. I plan to try them next, myself.

Does Cary have a recommendation? They'll know if a certain tube is a better match.

Cheers.
If You have tried the JJs EL34L then I take it your amp can take EL34s. If so, then you might want to try the JJ KT-77s despite whatever controversy over quality you may have heard, they have worked well for me and my friends. I find that they are very big and rich sounding. It may be the warmth you are looking for. Then again I like the Blue Glass JJ EL34L, I am using them right now. Try www.eurotubes.com he has them in matched quads for a low price and lightening quick delivery. I have no affilation with him just a happy customer.
Thanks to all. I have heard of the JJ Tesla KT-77s as an EL34 alternative. When I was trying EL34s (which turned out not to have enough power for my system's needs), a dealer suggested I try the KT77s. I'll go back and look them over, see what the power ratings are. If I use the lower-powered tubes, I can perhaps compensate by switching the amp to ultralinear mode, which allows for more power though it usually doesn't sound as good as triode. Regarding the issue of KT88s--Cary ships this amp with the Electro-Harmonix tubes and I've heard some on their staff (and Kevin Deal of Upscale Audio) likes them a lot. I'll call them Monday for a view. Very nice of all of you to respond with your suggestions.
I think you are describing the sound of the CAL cd player, not the amp! I did not own the model you own but I owned several others and while they were great in their day, over time they sounded mechanical compared to newer models. That was my experience anyway.

Art