Difference between Luxman L-550A II & L-507u


I was wondering if anyone has heard both of these Luxman integrated amps, and can comment on the sonic differences. I have heard the L-550A II and the bigger 590 and was very impressed. I'm seriously considering getting the 550, but just read about the 507 and am curious. It's not on audition close to me, so wondering if anyone can chime in (and not just a guess about Class A vs. Class AB, but actual experience).

Thanks!
brookjoo
507u is quite a big jump from 505u in terms of driving capability, clarity, depth of the stage and the overall smoothness. my local dealer here have all 505u,507u,509u, and 590A II in demo. i was lucky to have a chance to do a/b/c/d/e comparison with all of them along with a gryphon diablo. before i went there i was targeted at 507u simply because i thought it has newer circuit board, only 10w difference with 509u and it's 2.5k cheaper. the speaker was a pair of triangle megallen bookshelf, cdp was a luxman d-08. i first listened to 507u and overall i was quite satified though i found it was a little too ss sounding for me. switched to 590A II, 590AII had a lot more body and weight in the sound nodes, its definitely a thick sounding and musical amp. the 507u did better on high/low extension but could not match the well defined sound nodes and smooth presentation of the 590AII.

and then i switched to 509u, i was confident to say 509u was in complete different class with 507u and 590AII. it had the smoothness and body just like 590AII with just a tad thinner sounding. soundstage was so open with a lot more depth, what i liked the most was the authorities and powerful control of the entire frequency spectrum that you could not find in 507u and 590AII. 509u was able to portrait a complete stage while listening to orchestra. high/low extension was extremely well and stable.

i finally bought 509u even though that was out of my budget but at the same time it did so well that was beyond my expectation and now i couldn't be happier. i compared it with gryphon diable and i would say they were in the same class. gryphon had more powerful bass and sedutive vocal, however, it lacked depth, sound seperation was even worse than 507u and highs/details was not so great at all
Anyone hear or try the 550A with the Harbeth M-40.1's? I'm thinking a 20WPC integrated, albeit conservatively rated, would have a tough time pushing 40.1's 12" woofers.
Thanks Brookjo for your comprehensive review about the difference between the Luxman L550 and the Luxman L505u.

Within a few weeks I am going to buy one of these. Mainly I listen to classical music, especially organ, but also classical works with vocal solists, sopranos in particular.
So far I think I go for the L550a.

You'd helped me with the review. Thanks again.
Please tell me when you have any tips for purchasing one of these aplifiers, concerning other reviews, warnings or recommendations. Peter Roek (The Netherlands)