New Bel Canto REF600M using NCORE

Wow!!..Looks like John hit another home run at Bel Canto with the just released REF 600M using NCORE amplifiers. 300 watts into 8ohms. $4500.00 a pair. The REF 1000M is out of production. I have a feeling this is Bel Canto's best amp ever below the Bel Canto Black. Look forward to Guido checking it out.
Hey Audiozen... Good find! I'll have to check this Bel Canto REF600M baby out.

Meantime, here is the REF600M home page:

Best, Guido
From Bell Canto REF600M specification/features page:

"The Bel Canto Impedance Optimized Input Stage is a balanced high Common Mode Rejection, low output impedance driver that is critical to the amplifier's performance, ensuring that the refined dynamic qualities of the recording are preserved."

This is what will give this amplifier its "bell canto flavor", and separate its performance from the rest of the Hypex based designs.

BTW I listened to a system using the NAD M22 two weeks ago, and wasn't impressed. The comparison was against an Accuphase integrated costing twice the M22, but not a lot more than M12 + M22 combined.

Is it just my experience, or Hypex (in general) requires very, very careful matching upstream? (downstream they are as speaker independent as I ever heard).

I would love to hear other users experiences.
One minor correction regarding the price, the new REF600M mono amps list for $2,495 each. They are currently shipping but I haven't had the opportunity to hear them yet.
Sebollo, M22 and Bel Canto Ref600 are completely different designs... Different manufacturer, different circuits, and likely different modules. I would not venture to guess sound of REF600 based on listening to M22.

In general, NCore tends to have a high input impedance, hence compatibility with upstream devices should not be an issue. REF600 in particular, seems to have an input impedance of 200KOhms.... So upstream compatibility should be a non issue.

Downstream, NCore appears to have a damping factor between 500 and 1000, so it is possible that it works best for speaker with normal or lower input impedance... For my Vienna Die Muzik, NCore is a wonderful match.

Regards, G.
On paper the upstream and downstream matching possibilities with these newer ref600s is not really much different than current ref1000m I own. These match and perform well with all speakers I use them with and with most any input. I use 100Kohm unbalanced inputs though 200Kohm balanced is also possible. So these match well with most anything up or downstream but of course the exact nature of the sound will vary greatly still case by case as is the case with most any good quality amplifier.
I'm sorry if my post was not clear. I was not referring to NCORE impedance matching, as both the DIY NC400 and OEM NC1200 designs have all over 100K Ohms and don't present a challenge to the line stage devices.

I was talking about matching or pairing in terms of tonal balance, upstream. NCORE seems to be so neutral and with such an extended bandwidth, that it won't forgive not selecting the right source or line stage (by "right" I mean whatever makes you enjoy, feel the music you like).

NCORE, UcD as well as almost all the high end Class D developments were born, designed and optimized with professional audio performance objectives in mind. The first "audiophile" tuning has to be introduced by the OEM by designing the input stage (sometimes known as the brand sound), and finally completed by the user by choosing the right upstream components, also considering the speakers and room characteristics.

IMHO, it seems that NCORE, being so transparent, makes it a bit more challenging that final "user" tuning. However, if done correctly it can prove more rewarding.

The comment about the NAD M22 was just that, no intention to direct compare with the new Bel Canto amplifier, but in the general Class D and specific NCORE discussions it is worth to notice that it is not very simple to introduce an NCORE based amplifier in a playback chain and expect warranted satisfaction. I tried the M22 with a MacIntosh CD player and tube preamp, the speakers were Dynaudio Confidence C1 MK2. The result was a bit uninvolving, could not get the emotional connection with the music, only admire the resolution and dynamics of individual instruments.

Downstream, I read good experiences using NCORE with a wide range of sensitivities (even 104 dB horns) and impedance speakers, it does not seem to be a problem there.

I think the key to a successful NCORE based system is upstream. And these, as well as Anaview and Pascal, modules are so DSP friendly, that it is only a matter of time until advanced DSP is introduced into hardcore, purits, audiophile devices. French Trinnov and some other brands are leading this trend.

Cheers, Sebastian
Hi Sebastian, now I understand.... And I agree completely with you. If a component is particularly neutral, the components upstream and downstream will be somewhat more responsible for imparting a "desired" or "undesired" flavor to the output.

In my case I have been very lucky.... My trusty old Esoteric X-01, Rowland Aeris DAC, and Vienna Die Muzik speakers match beautifully with all NCore based amps I have had so far in my system: Merrill Veritas, Merrill Teranis (under review), and my Rowland M925 monos... Of course, all this simply means that the sum of the parts match my own particular goldilockian bias *grins!*

Just for the fun of it, a couple of months ago, I inserted into the system my ARC Ref 3 linestage.... And guess what... The overall sound became instantly much darker, warmer... And yes.... Tuby. The changed was much more pronounced than what I would have expected from a linestage insertion. Not my prefered sound by any stretch, but it had great charm in its own musical way.

It will be fascinating to find out what Bel Canto REF600 does for living... And what subtle flavor it imparts to the NCore base. Knowing John Stronczer past accomplishments, I am pretty confident it will be a worthy amp.

Audio Vision in San Francisco is selling the REF M600 at a discount at $4590.00 a pair and Underwood Hi-Fi will also discount. Sure like to see the engine under the hood and look at John's latest magic he does with his added power supplies. Not sure if the Ref M600 is the latest NCore NC500
but Guido will confirm with his future review.
Hi Audiozen, I'll try to find out what NCore module there is inside REF500. As for power supply, I have heard that each mono chassis sports its own Hypex NC1200/700 SMPS, which is powerful enough to support even the full blown 400W 38A peak current of NCore NC1200. This means that the 300W/8 600W/4 at 27A peak current can be supported with plenty fheadroom to spare.

On REF600, John Stronczer seems to have concentrated his design work on the custom differentially balanced input stage instead.

One useful feature of REF600 is the internal DIP switch to change gain from 27dB to 33dB.... This will be quite useful for use with lower efficiency speakers, such as the Maggie 3.7, and probably my own Vienna Die Muzik which has a bit of a wilding impedance curve.

Hi Guido, very interesting your comment regarding the gain switch in the new REF600M.

As far as I know, the gain setting has more to do with the preamplifier stage than with the speaker load.

It sets how sensitive the amplifier will be, meaning how much voltage it will need at its input to obtain its rated power.

So, if you have a strong enough preamplifier, you can lower the amplifier gain and still be able to reach the device rate power, independently of which speaker you have connected.

The big advantage is that with lower gain settings, you maximize the signal to noise ratio.

I would like an even lower gain setting, as many new DACs have quite strong output capabilities nowadays. The new Benchmark AHB2 has three gain options, for example, with the lowest being 13 dB.

I'm not 100% sure, but I believe that for the REF600M the gain option depends on the Hypex module, so there's not much John can do in that respect.

Sebastian, gain option is featured on the official product specs listed on the device page. I suspect that if the switch were a no-op because of some inherent NCore limitations, Mr. Stronczer would not have bothered with it... But I will ask him directly when I talk to him next.

Worth pointing out that a gain setting is available on other NCore based amps... E.g. Merrill Teranis, and my own Rowland M925.

In the case of Teranis, to optimize interoperability with my Vienna Die Muzik speakers, gain was increased to 29dB with no ill effects... On the contrary... Noise level did not grow at all, nor distortions were introduced... But that's the topic of a different thread.

Spoke with John Stronczer, he confirmed that REF600 has an internal 27/33db dip switch. According to him, the higher gain may be particularly indicated when the amp is driven directly from some lower gain DACs.

John has also confirmed that each REF600 chassis sports an NCore NC500 amplification module, in addition to an NC1200/700 SMPS.

Eventually, I hope to be able to listen to the creatures in my own system.

I've had my demo pair of the 600's for a few weeks now. Very impressed so far. Still likely need a few more break in hours on them, but they are quite good.

**Bel Canto dealer disclaimer**
Goldprintaudio, how do the amps compare to the REF500Ms?
Savjam - I would also be very interested to hear Goldprintaudio's more detailed comparisons. You should be aware that BC feels that the REF600Ms are a significant enough improvement over their previous top models to have replaced both the REF500M and REF1000M in their lineup.
I agree with Bill... With the premise that I have not heard REF600 yet, I have found REF1000 Mk.2 to perform comfortably above REF500... And every NCore amp that I have listened to this far has comfortably outperformed the admittedly lovely REF1000 Mik.2.

Hence, I conjecture that REF600 likely outperforms REF500 on all audible parameters.


Can you quantify in what way the newer model would outperform the older ones?

Of the 3, Ref1000m would still seem to have to set the mark for wattage.

600 is newer Ncore versus the others older Icepower, so apples/oranges there.

I would expect newer Class D modules within a line should outperform older in terms of bandwidth, etc. as the technology improves.

Then there is always how each "sounds" which is more subjective versus performance which typically must be measurable.

I own ref1000m. How it sounds exactly is a function of teh entire system playing. How it performs is not.
Hi Mapman.

Yes in theory you are correct... ICEPower 1000ASP, at least in theory, supplies 25% greater power than NCore NC1200. In my own system, NC1200 amps tend to create even more authority, a larger stage and images than 1000ASP machines... Go Figure!

In my own system, in terms of audible intermodulation control, REF1000 Mk.with its custom input stage 2 did a fine job at freeing the treble region from jarring artifacts. Rowland M312 with its more sophisticated input stage, custom SMPSs and PFC rectifiers did even a little better. Yet, Veritas, which has no custom input stage to speak bout, and uses a stock non-regulated Hypex SMPS, is virtually free of audible intermodulative artifacts short of some rare boundary conditions.

And then I could talk about harmonic exposure, micro detail and micro dynamics, and the sheer joy of listening to emotional music.... Which a very small number of older ICEpower amps deliver through a lot of ingenuity of their designers.... While NCore modules seem to be able to surpass even through some of the simpler amp implementations.

Does this mean that ICEpower is passed history? Not at all... I am sure that ICEpower will once again rise to the forefront with new offerings... Just not in any amps I have heard yet.

From what I read, NCORE (and also UcD) seems to be sonically step above what ICEpower currently offers. But there are other class D manufacturers that are also getting rave feedback, namely Pascal and Anaview. Many people say they are also sonically superior all ICEpower implementations.
I think this is expected, as Hypex, Pascal and Anaview designs are a generation ahead of B&O designs. As Guido commented, probably ICE next generation will get better and may even be sonically preferred over current top choices.
Everyone should try before buying these amplifiers. In many cases, due to upstream components, speakers, room accoutics, etc, the difference between a good ICEpower and an NCORE amplifier may be unnoticed.
Finally, and very important to notice, class D is still evolving. In two years we can expect a new performance jump from several of the many designers. In this scenario, it is critical to try before buy, and maybe target to at least a two generation jump upgrade.
I also have a 60w/ch bel canto c5i to compare. this is current model still also with ice power.

Also recently I've auditioned rogue Sphinx and pharaoh integrated.

I could easily live with any of these though none sound exactly the same they all perform quite well overall. I have never attempted an ab comparison. Just a general determination of thumbs up or thumbs down. Thumbs up for all! I can't see ever straying from class d at this point unless some sexy set or something totally new and different sucks me in someday.
Sebastian is correct... So one more datapoint... ICEpower has not been relegated to the refuse-pile of history by any means... There are today new amp designs based on newest ICEpower modules that are said to have amazing musical performance. One example is the Rowland M125 bridgeable amp.

M125 is not a competitor of REF600... Less power and smaller power supply capacity... But I have heard reports according to which this is also an amazing sounding little amp... Sorry, I have not heard M125 yet.

You know I listened to the JR M125 in my system and thought it was great. The M125 does everything very well, but doesn't provide deep bass. It's so good to me, that it convinced me to pursue higher end JR amps and ended up with the JR Continuum S2. I submit the M125 is great for small rooms with monitors.
Hi Richard, you are absolutely right, M125 does not deliver the current required to drive demanding speakers like your Ariel 7Ts... It is more suited for speakers with more moderate handling requirements.

Sorry for the late response guys.....I actually really still need to put more break in hours on the 600's to get an over all feel for the amps, but so far, I would say as good as the 500's where (I preferred the 500's over the 1000's), the 600's do seem better (even at this early stage). They are even more towards the "warmish" midrange/top end sound that the 500's were pretty good at. Also seem to have extremely good control of the bottom end with a more solid bass response.
Forgot to mention detail retrieval as well....I do think the 600's are a bit more detailed over the whole spectrum versus the 500's.

As noted above, Bel Canto does feel that these are the best amps they have built (not counting the Black amps). These are trickle down tech from the Blacks.
Hi Taylor, how many hours on your REF600 pair? Seems to me that the NCore NC500 module might require at least 500 hours of signal grinding in order to deliver its very best performance.

Hi Goldprintaudio, thanks for the report. Can you list the specific components you are listening the REF600Ms with?
Since I'm a dealer, the equipment list varies quite often. The amps are currently loaned out to a customer, but I was running them in with a Bel Canto 3.7 with a Sonos Connect streaming Deezer. I had both DeVore 3xl's and Joseph Pulsars hooked up so far (also Alta Lelantos for a bit).
Hi Goldprintaudio. It's been several weeks since your last post. Have you listened to your REF600M's recently and has your customer who had them on loan given you an evaluation of the amps?
Please don't push that dead horse off the cliff it might still be ali.... Since there has been no outside post on this thread since July I thought I might upload a topless girl holding a Bel Canto Ref 600M in each hand with a quote saying "Look at those Bel's!!" hoping this might revive this thread. Hey Guido or anyone else, any updates on Bel Canto's best budget amp ever?
With only two days of break in, I can tell these amps are something special. They are very rich, detailed and musical. The treble is fabulous. May be best of show at RMAF.
Great to hear. Thanks for the feedback. Could you comment on their performance relative to the REF 500m?

Mark - Would you please share what speakers you're using and what other amps you've compared them to. TIA!
Knowing bel canto I would expect their latest generation of technology to set a very high bar.

I run ref1000m mono blocks in one system and c5i in another and both are already pretty top notch to my ears.
Of course, things made in Minnesota are always best .
Yes lots of great audio gear out of Minnesota over the years. 🔊
Bill k,

There are too many confounding factors to compare the new REF600Ms against other amps. I replaced my dac at the same time I installed the amps: Bel Canto DAC2.7.

I have owned VTL, Cary, Nuforce, Marantz Reference Series MA-9S1, and others. What I can tell you is that this system, with DEQX and Joseph Audio Pulsars sounds terrific. The sound is richer, more detailed, and has wonderful treble. The cymbals shimmer, with decay previously missing. The singers' voices are easier to understand, and there is no smearing or harshness to their voices.

You should hear them in your own system. Color me very pleased.
Mark - thanks very much for sharing your impressions! The Joseph Audio Pulsars are definitely outstanding speakers.
I just received my second pair of REF600M amps.
It appears that the Bel Canto REF600M will go down as a reference statement piece and will sit on top of Everest as the worlds finest Class D amp in its price range. With that said, another reference statement component that was also released this summer several weeks before the Bel Canto REF600M, is the new SST Phoebe II Preamp from Spread Spectrum Technologies. I actually have heard this preamp through a pair of Emerald Physics speakers from a Wyred 4 Sound amp on the low end and the SST Son of Ampzilla II amp for the mid-range and a Wyred 4 Sound DAC. One of the very best preamps I have ever heard during the past thirty years.
A mind blower. Jerry Siegel's recent review and statement in 10 Audio online magazine, that it equaled the performance against the Levinson 326S at $11,500.00 and the $30K Levinson #52 with superior dynamic performance over both Levinson's. What really struck me is its remarkable organic smoothness, especially the high frequencies. Its holographic imaging, hall effect, echo decay, and its very three dimensional mid-range bloom, like the very best tube preamps on the market. The SST Preamp is derived from the Ambrosia Preamp. James Bongiorno and EJ Sarmento were working on these pieces together until James death, leaving EJ to finalize the designs with remarkable results. This Preamp has a very low output impedance of only 50 ohms, making it ideal to drive any Class D amp on Planet Earth.
This Preamp is a perfect match for the Bel Canto REF600M.
We have a demo pair in now and are just starting to put some hours on them, but already, these are quite a step up from their previous generation of amplifiers. They're detailed yet incredibly smooth with plenty of power, control and authority on the bottom end. There's a richness and naturalness to the presentation. Nothing remotely hard or fatiguing on the top end without sounding rolled off either. Very impressive so far driven by a Bel Canto DAC3.7.
Hi, has anyone compared the REF600m with JC1’s? I am considering moving to the REF600m from my JC1’s. I am wondering if it would be a step up in SQ or about the same? If its either a step up or comparable then I will be making the switch. I love my JC1’s but they displace too much heat and I live in Arizona where our summers are HOT! I have owned the REF1000m and REF500m and I loved both these amps. I have tried W4S SX-1000 which I liked too. I didn’t have the best luck with D-Sonic M3-1500m. The M3-1500m sounded way too bright and cold with my setup. I currently own Salk Soundscape 8’s and have tried the amps mentioned with the Salks and also with my Dynaudio C4’s. Bel Canto comes closet to Class A/B sound that I experienced. A nice warm neutral sound with good tight bass is what I have experienced with Bel Canto’s.
I haven't heard the REF600M myself, but all accounts I've read from those that have claim that they are a significant step forward from the previous BC models. The company felt so strongly about it to discontinue the more costly REF1000M since their newer REF600M outperformed it. That's quite a statement of belief in the newer product. Of course you'd be best off auditioning them in your system if possible, but it seems a pretty safe bet that if you liked their older series you should love the 600Ms.
This is the first review I've seen of them. He seemed to like them, although not enough to push his Anthem's out the door.
Thanks for posting the link to the Soundstage HiFi review of the Ref 600m. I find the reviewer Roger Kanno's following statement a bit curious:

"And as good as the REF600M was, it couldn’t equal the sound quality of the more expensive and more powerful Anthem Statement M1."  

I know that is quote mining and Mr. Kanno DID enjoy the 600m, but I find it curious because Kalman Rubinson of Stereophile reviewed the Anthem and ultimately concluded, "... in its present state I cannot recommend the M1. It imposed a tonal signature on the sound that was simply not neutral. Many successful audio products fail to meet this criterion, and some are perhaps designed to do so, but I don't believe that this was Anthem's goal."

I actually think that might be one of the harshest conclusions I've ever read in Stereophile. Take all of this with a grain of salt and throw in a dollop of "whatever floats your boat". I just find it interesting. For me, Stereophile is my most trusted resource outside of simply listening myself. I'm still riding the Ref 600m hype train and looking forward to auditioning soon. 
Kalman Rubinson reviewed the Bel Canto Ref 600m in the October 2016 issue of Stereophile! I got my copy in the mail on Friday. Another positive review and a place in the Class A list of Reccomended components. 

I listened to a promo pair of these a few months ago, and I was finally impressed with the sound of Class D.
But they were driving expensive two ways with an easy load, and in particular the ribbon tweeter was a nice flat 6ohm load impedance and flat small negative phase angle, which can to my ears make Class D sound not so good if it wanders too much in impedance and phase angle. So I wasn't sold, and have no opportunity to hear them on something more taxing to Class D. in the HF
From what I gather they do stray from just the off the shelf NCore design, as I believe that Belcanto have do their own output filtering which is tricky, and from what I gather it's a few series up filters so they can still push the power though them without blowing them, yet get a sharper rolloff to get that nasty switching noise killed off without effecting the audio band too much. But then series'ing up filters has it own set of problems, eg ringing again?? At least their trying.

Still to me the best way is to increase the switching frequency at least 5-10 times higher than what technology can do now. Then in the future when the technology allows this to happen,  just a single filter will do the job of killing the switching frequency noise without it's artifacts being anywhere near the audio band. 

Cheers George   
I currently have a pair of Pass Labs XA160.5s and my speakers are Martin Logan Summit Xs. How would the REF600M compare to the XA160.5s. Would be nice to have cooler running amps. I don't want to sacrifice the SQ.
I would stick with the XA160.5's as the ML's like all of them go down to 1ohm in the HF and this is where Class D has real problems.

Cheers George