Luxman 507uXi vs. Luxman 507uXii

Basically there really only is once difference between the two as far as I've been able to tell after listening for a while. The bass is even tighter on the Mark II, just a bit more resolution to it. But the original 507uX never really suffered in that department, so it's a minor improvement.

At 3600 bucks, brand new from Mike Rose as advertised here on Audiogon, the unit is a steal. You will not find a better sounding integrated for anywhere near this price unless you want to deal with tubes, then I'd get the Audio Research VSI75 which can be had around the 4000 range. Believe it or not, the bass is as tight on my Aerial 7Ts beeing driven by AR VSI75/REF75/VT80 as it is driven by Luxman. Where I feel it AR gear is superior to Luxman is 3D holographic soundstage. Not that the Luxman soundstage is flat by any means, but driven by a Chord DAC, AR VSI75 is just sublime.

Fun thing to do with your Luxman, being it has PreAmp out and AmpIn, is to stick a tube buffer between, like ifi iTube 2. It's subtle, but you get a bit of tube magic without the pain the ass of large tubes.

@hoopster One of these days I will put my collection of NOS Amperex EL34 up for sale. I've got 5 or 6 NOS matched quads. Best EL34 ever made. I wonder what a quad of them goes for these days.

@hoopster The EL34 that I find surprising value that can still be had for next to nothing is Japanese Matsushita. I have a couple of quads of them and I swear they sound just like a Mullard XF2 for a third the price. I'm probably never going to sell that collection even though I currently do not even own an amp capable of playing them. Same with all mine 6DJ8 and 6922s. They just collect dust for now, but it took me forever to build up the collection and I'm sure I'll get another amp eventually.

@erik_squires 

There is a bit more to that than that. I've had both. Recently sold the 505 and replaced it with 507. The preamp section of the 507uX is better as is the output stage. How much better? Depends on the speaker. Not much of a difference on Aerial 5Ts. Much better bass grip and bass to lower midrange integration on Aerial 7Ts. 507 doubles down into 4ohms. 505 doesn't.

@hoopster Congrats. You'll like it. Sitting here working right now listening to my 507 on Aerial 7Ts/Aerial 5Ts. Nice to have speaker switch depending if I'm at my desk or coding away on the sofa. Aerial's 5Ts and 7Ts are all the speaker I will ever need. Still waiting for a good deal on 6Ts to show up to use for surrounds in my HT. Currently I'm using 5Bs.