Mu buddy has the Luxman 595 and is a former owner of the 590 AXII. The difference in price is justified according to him. Here is the list of differences.
What we understand is that there are over 120 parts detail differences between the L-590aXII and L-595ASE;
* Different main power transformer, with special attention paid to noise entering the circuits. And with special vibration control of the transformer itself.
* New, special power supply capacitors. Also installed with special vibration control mounting.
* Anti-resonance chassis design elements implemented in the extreme.
* Peel coat PCB’s implemented where it can make a difference.
* Special copper clad critical signal path shielding.
* Special “Line-1 gold direct onto copper (KAPPA) alloy” RCA style input jacks. (For best sound quality)
* Special selected Nichicon and Nippon Chemi-Con capacitors used throughout.
* First introduction of Luxman’s proprietary “ODNF-u” (Only Distortion Negative Feedback – Ultimate) in an integrated amplifier application. (An advancement over ODNF 4.0)
* Special, very low -impedance speaker relays. (Higher damping factor= 370)
Problem with CODA (if you consider this a problem) is resale value. You’ll get crushed if you buy anywhere near MSRP. Coda has far fewer dealers than Luxman or Pass so you can get better discounts with LUX/PASS than you probably will with Coda. I have Coda 8 + 7 Pre-amp so Im certainly not a Coda basher. I bought the pair for around 6K combined with only 6-9 months of use on them when they were listed. Think the MSRP is 13-14K on the pair. OUCH!