Luxman m-900u owners - quick question

Mine is here to stay. May be the best value uktra high end amplifier. Very tuby highs, world class solid state resolution and dynamics, huge soundstage. A lot of meat on the bone midrange. Class A up to 12 watts wich is huge. 

Emit some heat even at idle.

Hello techno _ dude ..thank you and what pre-amp are you using ?

Mac C52

There is a lot of discussion on the Luxman m900u on this thread.

https://forum.audiogon.com/discussions/my-long-list-of-amplifiers-and-my-personal-review-of-each

Yup, whitecamaross is your go to guy for this beast

I have two setups, each with an M900u in the chain. Only one of them is with a C900u. Both setups use a Chord Dave as a source. Running the dac directly into the M900u is a different sound than through the C900u preamp. To my ears it requires a quality preamp like the C900u to unlock the fullest potential of the Dave. The sound with the C900u in the chain creates a more dynamic and palpable sound with more texture. Running the Dave directly into the M900u works fine, but it doesn’t have the same emotional impact, and I have a harder time connecting to the music. This is of course just to my ears and YMMV etc.

Have you considered an used M800A?, puts more in Class A (and heat) than M900u and outperforms its own spec by margin as measured by Stereophile. 

I also have M900U and C900U. Had Jadis and other hi quality tube amplifiers in the past and now switched with the Luxmans to SS. I am very happy.   

@garebear did you ever hear about Coda 15.5?. Class A up-to 100 Watts into 8 Ohms and then Class AB till 150 Watts into 8 Ohm, less than 50% retail compared to Luxman M-900u btw. If you want to compare options and want first watts to be pure Class A.

I can concur with nebob's findings but while driving my M-700u with a Chord Dave versus the C-900u.  The Dave was slightly more immediate sounding but ironically at the expensive of the utmost control of the stands of the music. Soundstage with the C-900u was also much more enveloping, with greater ease yet oddly more drive to the music. I also found that the C-900u conveyed all the detail of the Dave in a more emotionally engaging way, effortless.

Re: m900u with a different pre, has anyone figured out how to trigger on/off from a pre with standard 3.5mm trigger cable output (ex McIntosh)?  The m900u trigger input looks more like a phone jack.  Thought Blue Jeans Cable in Seattle might be able to build a custom 3.5mm to rj11 if I knew the wiring.

I am currently using the M-900 U , just turned it off. I had the preamp first  and just got the amp 2weeks ago  and still have questions. First if a AB amp has to run so hat why design it in such way that it delivers only 12 or 18 in class A. Is it just to adopt the hyper-modern look and restricted ventilation?The  Amp sounds very detailed and solid  with no harshness  Still under evaluation with his Luxman peers . I am a dedicated Luxman fan This amp  is playing substitute to a pair of M-5 run in Vertical bi-amp( 1 stereo amp on the left the second on the R)
cannot afford 2 M-900 U now. !!! This set up alternates with also two M-05 100 pure Class A run the same way or at time two Accuphase P-102 .  I just got rid of two old  M-22  used in the same set up on the speakers that I have for 17 years the Piega. C-35 . Still evaluating . I do not believe in reviewer like statement best amp  ever At this level  great amps may differ in some points may be this is all there is to it at this level of High-end. Believe me the tonalité and the thightness of the bass and mid bass with the 30 watts class A Pioneer M22 is not something to sneeze at even at this level

I am currently using the M-900 U , just turned it off. I had the preamp first  and just got the amp 2weeks ago  and still have questions. First if a AB amp has to run so hat why design it in such way that it delivers only 12 or 18 in class A. Is it just to adopt the hyper-modern look and restricted ventilation?The  Amp sounds very detailed and solid  with no harshness  Still under evaluation with his Luxman peers . I am a dedicated Luxman fan This amp  is playing substitute to a pair of M-5 run in Vertical bi-amp( 1 stereo amp on the left the second on the R)
cannot afford 2 M-900 U now. !!! This set up alternates with also two M-05 100 pure Class A run the same way or at time two Accuphase P-102 .  I just got rid of two old  M-22  used in the same set up on the speakers that I have for 17 years the Piega. C-35 . Still evaluating . I do not believe in reviewer like statement best amp  ever At this level  great amps may differ in some points may be this is all there is to it at this level of High-end. Believe me the tonalité and the thightness of the bass and mid bass with the 30 watts class A Pioneer M22 is not something to sneeze at even at this level. My question any idea why this 900-U run so hot as a AB amplifier most good amplifiers have their first watts in A nothing new here Why it gets so hot?

@mocassin2     Congrats. on having such a fine amplifier!  Luxman gear is very robustly built all across its product line.  I have the E-250 phono preamp and it really allows me to hear the best that my vinyl has to offer.
As far as the M-900U running hot, I would be shocked if it didn't.  For an amp that's putting out 150 watts/ch. into 8 ohms to be able to put out 1200 watts/ch. into 1 ohms it is a very high current design and thus will run hot.  Looking at the chassis on the Luxman site, the heat sinks though heavy duty, are encased inside a thick aluminum shell.  So the heat being dissipated by the heat sinks is trapped in the amp's casement and thus makes the chassis hot. 

The good news is that Luxman must know that their amp. will be on the hot side and therefore have designed the amp's components to be able to work appropriately at that greater temperature.  My amp runs on the warmer side, making my listening room comfy in the winter months.  As for the summer, thank God for air conditioning.😛

a truly great amp. if you can afford a c900u you’ll never look back. please don’t use a dac direct into this amp. just doesn’t sound comparable imo. and please don’t consider a mac pre with this amp. it deserved better. 

@4425  What about a more neutral and quieter preamp, instead of the Luxman c900u, such as the Benchmark LA4 or Mola Mola Makua preamp. It is not so much a question of funds for me but the issue of number of boxes in limited space. I heard the c900u + m900u and it was amazing. 

Someone did tell me the Makua sounded better with the m900u than the c900u but that opinion is a bit biased.

By looking through the top I got a sense of the size of the heatsink but it looks like they wanted the entire chassis to radiate the heat. It beats the M—05  (100 Pure A )that I still love :sweetness over details !!

By looking through the top I got a sense of the size of the heatsink but it looks like they wanted the entire chassis to radiate the heat. It beats the M—05  (100 Pure A )that I still love :sweetness over details !! By the way I don’t think driving any amp in this class with any DAC directly is a great Idea 

to answer question above in my opinion you do not have to use only the c900u with the m900u. the m900u is transparent with no coloration that i can detect in my system. just be sure to not diminish its abilities with a weak front end as the Luxman will let it through. 

Tried a m900u on my YGs and while it had nice tone and texture, was kinda limp and non dynamic with no bass. My guess is I would have required monos for my tastes.

beautiful unit though 

@keithr

Was this the 2 way YG with the cap in the bass? If so, yeah, I imagine a high impedance (i.e. tube) may work really well for you. ;)

No, the Hailey

I’ve owned the M900U for six months now. I’ve purchased over 30 amps in my lifetime and it’s clearly the best I’ve ever owned. I leave the unit on all the time and mine never gets hot, just warm. Adequate ventilation is a must. 

@keithr what did you end up with ?

I wonder if the XP32 can give the c900u some competition.

The M900U is a very good amp. I owned it for 2 years with mixed feelings.
First, I didn’t care for it that much with the C900U. I felt it gave me too much of what the M900U already had to offer. To me the M900U wasn’t the most neutral amp I’ve ever heard. It had a character that was some what polished and not very analog sounding. There were times I felt like it was the best amp I ever owned (see my previous comments) and other times wished I never bought it. I’m sure in the right system it can be as good as people have described, but for myself it was at best, a very good amp.

Has anyone compared the Luxman top-of-the-range C-900U/M-900U to the L-590AXII or L-509X integrated?  Is there a noticeable step up in sound quality going from the separates to the integrated?

I went to an audio store to audition the 509x and I liked it. I was about to go home when the dealer said have a listen to the m900u/c900u. I had about 15 minutes to do this other wise I would get stuck in LA traffic for hours.

Big mistake. The m900/c900 was so much better than the 509x on the same system. I ended up staying about an hour + listening to that combo and tossed out the idea of the 509x. The m900u has much more power than the 509x. It was easily demonstrated on the TAD ME-1 monitor speakers that were hooked up to the system.

I did not get the m900u/c900u combo because I found something more appropriate for my smaller space. However, I may revisit the Luxman amp in the future for the bigger space downstairs. I will not get the C900u preamp since I will use a Benchmark HPA4 preamp from now on any system I build.

BTW - I had about a 3.5 hour drive home because I stayed longer to demo the m900/c900 combo. It should have been under 2 hours.

Thanks for the information yyzsantabarbara. I currently have the L-590AXII and the sound quality of the system is stunning. As the speakers don’t need the added power, I’m not sure if the C-900U/M-900U will make much of a difference. Will revisit the idea if there’s an opportunity or additional funds for hifi.

Nice story you got there for the long hours of additional drive home.

@ yyzsantabarbara

I am also thinking about the right preamp match for my Pass Labs XA 60.8. Current ideas are Pass Labs XP22 oder Luxman C900u or Benchmark LA4/HPA4. 
What is you experience with Benchmark preamp, especially compared to Luxman C900 and other preamps you heard? I think the Benchmark has a very interesting concept concerning volume control, which I think is crucial overall.

thanks, Robert 

 

I have the pass x350.8 and loved the sound of it but the problem is it heats up my bedroom like crazy and in summer its tough to run. I wonder if the luxman will run cooler than the pass and if it will be tonally warmer since im really chasing a rich tone right now.

@smodtactical 

I am also interested to hear how Pass compares to Luxman.

Based on what I’ve heard/read the 900u is not a punchy amp. The 350.8 seems to be fuller sounding with more bass.

They are identitically priced here in Sweden.

Interesting. I am guessing the fact that Jay likes the m900u so much that its probably the more forward / thinner sounding than the pass. Jay likes a very fast, hyper-detailed type of sound and that is definitely not my sound. But I have no idea, have not heard it.

Ref Luxman m-900u 12v trigger
 
The phone jack is actually a 12v trigger if you look in the cable plastic end yo will see a red and greed red is the positive do not connect in reverse.
You just have to make your own cable not that hard.
I tested it and it works but does not work with 5v  Mcintosh for that you can buy a cheap relay trigger off amazon with a 12v supply so the 5v will trigger the relay and the relay will send 12v to the luxman. Hope that helps