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.
audiozen
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**
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.

G.
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.

G.
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.

Rgds,
Sebastian
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.

G.
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 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.

Guido
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
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.
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.
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.
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.
Hey Audiozen... Good find! I'll have to check this Bel Canto REF600M baby out.

Meantime, here is the REF600M home page:

http://www.belcantodesign.com/eOne/products/amplifiers/ref600m-amplifier/

Best, Guido