Robert Lee recommends Triode Corp, but...

I am using Cary 805AD for AZ Crescendos. They are great together. You might look for older 805 for under $3K.

I own the a Crescendo speakers and use two amps to great effect. I find one amp has a group of strengths that no tube amp can match while the other amp has qualities no SS amp can match on these speakers. Don’t rule out SS.

I use a Lyngdorf 2170 which is a stellar Class D unit. The bass impact and control of the speaker is wonderful and better than the numerous tube amps I have put on the Crescendo. If I want a different sound that is more richly detailed and lite up from within, I use my highly modified Cary Rocket 88r. I find 30 watts in triode nice, but the speaker really comes to life with more power in my larger space. I know the builder says SET amps work great with this speaker and they do. However at 90db efficient and 6ohm I find they like more power than 30 watts or so.

Cary and LM tube amps are both highly recommended for you. The Cary Rocket 88r can be found used for under $950 and with some mods sounds very much like a powerful SET amp. Upgrade the coupling caps, remove every electrolytic cap in the power supply and replace with film caps. Use better hook-up wire in key spots and get SR Black fuses.

Let me give you another choice that would be fantastic on your speakers. Von Gaylord LM Triode monoblock tube amps. PP amps with 50 watts of glorious tube power and no mods needed. These are amazing amps and so beautiful sounding. Ray’s gear flies under the radar and is so very special. A set is for sale now for $2200 I think. Great buy.

You all are awesome for your thoughtful suggestions. And thank you in particular to the AZ owners for their ideas on synergy and cautions, too. Keep those suggestions coming in.

Again, My LSA is stellar, but in this hobby there's almost always the 'What else..." motif. Not the need for improvement or anything "better", but simply a curiousity as to what else is out there.

The same motif does not apply, of course, to my marriage.

I drove my Acoustic Zens with a Triode of Japan Intergraded 300B with only 8 watts. I'm not using the Amp anymore since changing speakers, If interested let me know.