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).

I'm a Luxman dealer so take it for what it's worth. I'd forget about the class A vs AB. I'm still struggling to tell which models I prefer. Hearing class A many think that means better and it may in many cases but the Lux AB stuff is equally good to A just a bit different. Without getting to audiophile. The Class A Lux is what you would expect. Bit more romantic. Lush etc. Warm without being too warm. The AB hits harder and is more dynamic. But sitting in front of both, you'd be hard pressed to pick one type. They are both quite amazing. For example, I prefer the AB stuff on a large speaker such as the Harbeth 40.1 and the Class A on say an HL5. Just for sheer control and authority. Both are equally refined. Bottom line, you pay big bucks for small gains in audio Is the 507 worth the extra over the 550. In many instances I would say yes. The 507 is more detailed and refined as it's a more exact piece. I could live with either.
Thank you for the detailed answer. Since you are around both pieces a lot, could you tell me about the heat output? The 550 ran pretty warm, but thankfully not as hot as the 590. How is the 507 in terms of heat? Also, any feeling about the onboard phono stage?
Harbeth has been on of the brands I"m looking at (probably HL5) and Devore (gibbon super 8 or Nines). Thoughts with either Luxman?
I have the L-550IIa and Harbeth SHL5s ... wouldn't trade the combo for anything at this point. Did a lot of searching.
i had a chance to do an A/B comparison between 590AII and 507u, the setup was with a luxman d06 cdp, proac D18 floor standing speaker..the result is quite similar to what Dkasab described above, 590A II was lusher, warmer, slower and thicker sounding than 507u. 507u had better image, faster sounding, a lot better in dynamics and attacks and better detail(i could hear clearly the sound from the backstage)..my speaker is b&w 805s so if i were to get one, i would pick 507u..which was a complete different story when i tried Accuphase e-450/e-550...i'd prefer e-550 a lot more...
Hello Dkasab

I'm same boat, trying to decide between the 505u and the 507u.
I have heard the 505u and like it quite a bit.
But is it worth going to the 507u ? that extra 10w at 8 ohms ?
Thanks for the inputs.
Thanks everyone for writing back. I had both the 505u and the 550A II in my system and wanted to briefly post my results. First off, both are fantastic and I could easily live with both. As is always the case, it comes down to my own listening preferences (both in terms of type of music and kind of sound) combined with the rest of gear.

The 505u was very dynamic, with tuneful, deep bass and shimmering highs. It had more than enough power for my Devore 9's, and as with the 550A I feel like the wattage is very conservatively rated. Pace was particularly good, and the sound was very engaging. My little digs, which again are only in comparison to the 550A, are that the speed and dynamism of the 505 seems a little over-kill at times. Cymbals have a little too much attack, and in generla it feels like the leading edges are favored too much, making things almost sound too zippy. This was apparent in violins, which didn't sound as pure as with the 550A. This also makes the 505 sound a little hi-fi than the 550, which sounded more natural to my ear. It's almost like when you see really good computer animated versions of humans, and it's really cool but also a little creepy or not right. This is a REALLY minor version of that, and only by comparison, but in the end the 550 seemed the more human of the two.

The 550 was definitely preferable on the top end for me. It didn't have extra sizzle of the 505, but I found that a much more natural presentation. Furthermore, the bass, while not a zippy as the 505, sounded more like an actual instrument, than a recording of one. It didn't sound thick to me at all, just fuller, in a truly satisfying way. Vocals sounded hollower on the 505 than the 550, as did strings.

So, to make a long story short (and if anyone is interested in my notes, let me know and I can forward them on) I thought the 550 was a better choice in my system. If I had hard-to-drive speakers, I would without hesitation get a 505, or try the 507, but I'm lucky in that respect. Again, my digs at the 505 shouldn't be taken out of context, as it was a seriously good amp, but in the end the 550 was better by comparison.

Thank you for the detailed reply.
This is very helpful info indeed.
No worries Nolitan. I really think the 505 is great. You should also know that the difference between the 505 and 507 isn't just 10 watts. The 507 has better binding posts (look like WBT in picture, the newer distortion reduction circuit (ODNF 3.0 vs. 2.2, and another set of balanced inputs. Not saying that alone makes it worth the jump, but it is more than just a conservatively rated 10 W jump.
Who knows if 507u is closer to 509u or 505u in performance...
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
Oh wow, nice comparo!! thanks!! 509u is a bit out of my range.
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)