I have the 590AXII, its not a warm amp. Its a neutral amp that matches well with easy to drive speakers. The amp is very refined and detail, I've alwasy found Klipsch speakers to sound a little bright due to the horn tweeter. You cannot compare a class D amp with Luxman Class A. I pair my Luxman with Silverline Sonata II and they sound awesome. My Yamaha AS-3200 is warm sounding.
Experience with Luxman L-550 AXII
I'm considering the Luxman L-550 AXII to drive a system with Klipsch Cornwall IVs during summer months. My Class A 805 SET amp is a 100lb space heater and I dislike having my package AC unit on the roof of my music room running more just to keep up with the heat the amp creates.
I've heard some folks love the pairing between the CW IV and the LUX 550. I am a touch concerned though that this Lux might not be warm enough for my tastes. Although, I have tried a Marantz PM KI Ruby integrated that uses a Ken Ishiwata tuned Class D design that sounds lovely--despite my bias that it would sound too lean and cool.
I do prefer a little warmth yet synergy is everything.
Does anyone have experience with this amp? I know this is likely something that I'll just have to try out anyway but I'm looking for user experiences, thoughts, and even other recommendations.