Luxman tonality

I’ve seen many members describing the Luxman 509x and the m duo as warm thus colored. I’ve had these units and have never thought of them as bright or dark(warm). They are superbly neutral to me neither adding or subtracting. I find them to be very musical. A prospective buyer might pass on Luxman thinking that they won’t match up with many speakers. Of course they will. Neutral is neutral. It’s what we should want.

Compared to 509, the 590AXII tilts towards warm, but only by a smidgen. After living with it for a few months now, I would say the 590AXII is fairly neutral with just a hint of warmth. And as Eric said, the extension on both ends is really amazing.

I would agree with this post by Arafiq. Similarly I find the L-590AXII to sound very close to neutral, leaning slightly toward warmth. I have owned many amps in the past which include some costlier pre/power combinations and the Luxman L-590AXII is the first high quality integrated which I can live with for life. It may not be a Vitus, Gryphon or other uber-amps costing up to $30,000 but the quality really shows.

The Luxman L-590AXII sounds smooth, warm and natural whilst displaying good detail and a refined and nuanced delivery. The treble is smooth, detailed and illuminating without sounding bright or etched while the bass is very satisfying, showing good definition and detail. Basically a balanced reproduction across the frequency spectrum. I don't have experience with the L-509X but looking at your response I feel the L-590AXII Class A will better fit my Marten Duke 2 and listening preferences.
I’m not so sure that the top luxman integrated amps aren’t in the league of the more expensive brands mentioned. a blind listening test would prove very interesting IMO. Forget the prices and just listen. 

I’ve had a chance to listen to Luxman side by side with D’Agostino separates. These two are so much in the same sound family of sound quality.

However, no matter how much I like them there will be those who are going to be happier with something else. I think surveying Ayre and Pass along with Luxman will help clarify your tastes and needs.

For me personally, I really like Ayre, but it is not at all the same sound. If I had a chance of buying Ayre or Luxman’s best I’d be really torn. There are also a sizeable number of people who once they hear Pass cannot be separated from it. 

The good news is this:  No matter what I personally like I am 100% sure if you listen to these three you'll come up with your own winner.

well i lied. i think that the agostino progression integrated has the best mids that i’ve heard in an amp to include an ARC tube amp. however i need luxman’s treble control due to some high frequency hearing loss. yes i’d rather have the dag with a treble control but it’s not in the cards. 
i’m happy with my 509 and it’s about 1/2 the price.