Comments please on: NAD M23 vs c298 vs. other newer Class D


I'm interested in comments about the new-ish NAD M23 amp. It gets rave reviews on the Absolute Sound channel, by Doug Schneider and by the review at Sound Stage, and by others. Reviews describe not only an even response across frequencies, but layering of the soundstage (left-right and front-back) as well as excellent measurements. Some describe the sound as somewhat tube like in the mids and upper range, others as neutral, but all agree it does not have the harshness which typically characterized reports about earlier amps with this design.

I am not giving up my Pass XA 25, nor my QS Mono 60 tube amps. Or my ST-35 Dynaco. What I'm interested in is a another amp in the stable that can play nicely among different speakers (not all are as sensitive as my main 97db ones), and that might bring that snappy dynamic speed to the sound but without making me cringe from the highs.

If you have some opinion of this Eigentakt design, especially in comparisons to Atma-sphere's Class D or other amps with similar technologies inside, please comment. (PS Audio, Bel Canto, et al.)

If you have some opinion of the NAD M23 vs. the cheaper-but-still-Eigentakt NAD c298, I'm interested in that, too.

I'm NOT interested in super pricey amps. Say, above $8k

hilde45

To @hilde45 its going to be interesting if you proceed with a NAD M23 Class-D amp and compare to other Class A and AB SS and tube amps in your well treated room.  

While I’ve not heard one on my system, I do notice if I turn up my full home theater system and watch those higher definition videos with good microphones where they flip back-and-forth between the M23 and Pass Labs amps we both know well, the midrange body and weight of the M23 in the midrange is more bold and forward. No way to trust this, but I have heard this multiple times comparing other amps on these limited video recordings. Not a trustworth test, but it is A vs. B fwiw.

I wonder if that noticeable weight of the midrange and slightly rounded off top end of the M23 is apparent in several real-life listening sessions when paired with your SS and Tube preamps in your treated room. Will be interesting if you try this.   

Update: I got the NAD M23 to try out. Hesitant to say too much because I don’t want to prejudice myself, but so far it is more dynamic and detailed, including in the bass, than my other amps (Pass XA25 and Quicksilver Mono 60’s with KT77 tubes). I’m driving 97db speakers (15" driver plus AMT tweeter) and currently using the solid state preamp.

Sounds: 

Midrange sounds really nice. Not thin or analytical but definitely less warm and rounded. But much better than the Hypex I had in here.

Great energy with dynamics and transients -- easy to get the toes tapping.  Hearing some new notes (maybe even instruments) and richer textures in tracks I know really well.

A couple tracks pushed me back in my seat with some brightness -- but I’m pretty sure it was the volume setting and/or the track itself. (In other words, it would happen on other amps, too.)

Sound stage is really good so far -- perhaps less depth than the tubes, but I imagine that’s to be expected.  Need to listen more.

The big test will be to see if, over time, it gets fatiguing and if there is ultimately something that seems not very interesting about it. Performance wise, everything is going well, but it needs to be listened to for a lot longer, and it needs to be compared with the other amps, and it needs to be tried on the other speakers. If I’m going to spend $3000 on this thing, it has to pass a lot of tests. The most important test is that it has to be interesting and bring something new to the table. Otherwise, I’ll just wind up looking at it on a shelf, thinking about the hassle of selling it used. 

hilde45 - Nice initial feedback. What pre-amp and sources are you running? If ever an amplifier demonstrated ruler flat frequency response and nearly perfect measurements don't exactly produce beautiful results, the M23 would be the poster child for that category.

For me, I'm constantly seeking perfection in playback so I can tweak the other variables in my listening environment as needed if the I know the source is true. I find the M23 to nearly flawless on the measurments front, but understand that isn't necessarily the sound everyone wants.

Despite many seeking perfect measurments, I believe most are actually seeking listening bliss. Those are very different objectives in my opinion. Nonetheless, I am very happy with my M23 and am considering buying a second (pre-owned, version V1)  and running them as mono block amplifiers. 

It would be hard to find an amplifier that measures better than an M23. However, that clinical grade amplification leaves much to be desired for many audiophiles. A bit like a professional marathon athlete vs. Sydney Sweeny. One is the epitome of efficiency and performance. The other...

Which is the end game partner? The perfect athlete or the stunning head turner? Absolute performance vs. hedonistic pleasure? Do both exist in a single product? If so, please point me in that direction!

@connollymj 

At the moment, I am using my SS preamp, which is very quiet and neutral. My source is a dead quiet Pi-based streamer running Qobuz into Roon or streaming from an attached hard drive. Mostly, I stream.

Measurements (which you mention throughout your comment) are not important to me unless I find a way to hear them in my listening. So, no free ride for the M23, there.

"Listening bliss" is a good phrase. I’m interested in the varieties of bliss that exist. The Pass XA-25 offers one kind of bliss; the monoblock tube amps offer a second. The question is whether the NAD M23 offers a third, distinctive kind of bliss. That’s the objective of my listening inquiries.

The promise of this amp, and newer Class D in general, is a more articulate sound stage, snappier dynamics and transients, space between instruments -- all while delivering tonality and presence that has an emotional, not-clinical, engaging appeal. I don’t expect "warmth" (often the result of pleasing harmonic distortions that Pass and tubes give) but I’m expecting something approaching "intimate" or "organic" or "natural."

    

Paging Ralph at @atmasphere -

If Class-D amps can be carefully laid out in a stereo two channel format with "plenty of power", relatively low distortion, with careful isolation of components for each channel, in a shared chassis - what would be the Top3 reasons some manufacturers still choose to make Class-D amps as mono amps?

I realize your amps are set up like this is why I bring it up, and PS Audio does something similar. I wonder if you might be willing to present your case how your Class-D mono amps would surpass some of these mainstream stereo Class-D amplifiers?  Its a legitimate question.  For reference I’ve owned many SS and tube amps in stereo and monos and usually hear a compelling difference in Class A, AB tube or solid state mono amps to this day. I enjoy the channel separation mostly.  

How’s that work with Class-D amps with stereo vs. mono, pros/cons/benefits with Mono Class-D amps.- can you break it down for us as you normally do here on Agon?  Thanks in advance for chiming in.  :)