Bel Canto Design Black amplification system

Stereophile normally doesn't review audio systems. We review individual components. We've made an exception for the Bel Canto Black system because it deserves to be evaluated as such. It consists of three dense, almost identically sized cases of black-anodized aluminum. One, the ASC1 Asynchronous Stream Controller, is what in a conventional system would be called a "preamplifier." The other two, a pair of MPS1 Mono PowerStreams, would in a conventional system be called "monoblock power amplifiers."

However, the Black does not comprise conventional components. The ASC1 accepts AES, two S/PDIF, two ST, and TosLink digital audio inputs. It also includes an Ethernet UPnp/DLNA Media Renderer Input and a USB Type 2 audio input. There's also a stereo analog input (RCAs) that can be used for a surround processor, a conventional preamplifier, or even, the brochure assures, a phono preamp. A high-performance A/D converter chip, located within 2cm of the analog input, converts the analog signal to 24-bit/192kHz digital.

The ASC1 outputs the incoming digital signal at the latter's native resolution via a pair of StreamLink glass optical ST jacks. A pair of XLR AES digital jacks can drive a digital subwoofer or an outboard DAC. Bel Canto supplies lengths of fiber-optic cable to connect to the MPS1 inputs, a hefty remote control of milled and black-anodized aluminum, and an iPhone/iPad app through which everything can be wirelessly controlled via Bluetooth.

In other words, whether you live in the world of analog or of digital audio, or in both, the Black is ready for you.

The ASC1's digital inputs are isolated from chassis ground and the Ultra-Low-Noise (ULN) master clocks retime inputs, stripping out noise and jitter. You can choose among three Custom Time Correct impulse response, apodizing digital reconstruction filters, which will be most critical for CDs and CD-resolution files, or you can use the default FIR filter. A custom 32/64-bit DSP processor operating at 500MHz controls a 32-bit volume/balance control, the Asynchronous digital interface, the filters, and the generation of the Black's digital output, wherein the output is retimed using a high-speed memory chip coupled directly to the ULN master clocks.

The MPS1 monoblock has both balanced analog and ST-optical digital inputs. The latter can be assigned to either left or right channel data and asynchronously retimes the digital signal with the ULN master clock located in close proximity to the DAC. According to Bel Canto, the ULN master clock, located adjacent to the DAC, produces fewer than 35 femtoseconds of phase noise, which the company claims produces an analog signal of "utmost purity," free from "digital" noise.


The fully balanced DAC, which Bel Canto says combines "the best of multi-bit and delta sigma technologies," outputs a high current that's directly coupled to Bel Canto's proprietary, balanced, discrete current-to-voltage stage, followed by a thermally stable, high-current, class-A output that uses naked Z-foil resistors for voltage conversion and, for the analog filter, precision film capacitors. This stage drives a discrete voltage gain stage that outputs a fully balanced, 18V, high-current drive to a custom version of the Hypex class-D analog nCore module designed by Bruno Putzeys that's said to be capable of producing peaks of 40 amps into 2 ohms using only four high-current output MOSFETs that can deliver up to 1200W. Hypex supplies Bel Canto with customized modules designed specifically for the Black. The internal wiring to the WBT NextGen speaker connectors is by Kimber Kable.

The MPS1's power supply includes a custom internal AC power conditioner and a multistage hybrid switching/linear architecture with what Bel Canto claims is an "audio grade" switching supply dedicated to the high-power section, and the low-noise linear supplies used for all small signal application, both analog and digital.

To ensure the best performance from the master clocks and analog circuitry with the least possible noise, the ASC1 and MPS1 are enclosed in resonance-free mechanical structures carved from solid blocks of aluminum with constrained-layer damping. In the MPS1, each subfunction is encased in its own compartment,with the analog stages carefully "cocooned" from digital pollution.

And it all means . . .
. . . that the Black doesn't need an outboard DAC or expensive analog signal cables (other than to connect an analog component). Yes, it can decode DSD files. What's more, its ST fiber-optic interconnect means that the ASC1 can be placed more than 300' from the MPS1s with no loss of quality, no ground loops, and no interference of any kind.

The three-component package costs a total of $50,000: $15,000 each for the MPS1s, $20,000 for the ASC1. That makes it an attractively priced package in my corner of the high-performance audio world, where you can easily pay $50,000 for a pair of monoblocks that output far less than 1200Wpc into 2 ohms—and you'd then have to add a DAC and cables.

Setup and Use
The Black system was easy to set up—even an analog person can manage it. In fact, I had both my reference and Bel Canto systems available. Switching between them to make comparisons required only that I switch power cords and speaker cables between amps.

The ASC1 has a large, red-lettered LED display on its faceplate and, at the front of its top panel, a single, multifunction button/wheel. Rotate it to adjust volume, or briefly press down and rotate to change inputs. Hold the button down for a few seconds to enter Program mode; to exit that mode, hold it down again. buyers will use the Black's remote control or iPhone app. The latter is the easiest, most intuitive way to operate it: You can adjust the volume using the virtual wheel, select among inputs, soft- or hard-mute the output, change the ASC1's display, choose among the filter options, reverse its polarity, adjust the balance, name the inputs, and delete those you don't use.

Consider what you can do
Here's what I ended up doing: First, I ran the Tape Out of my darTZeel preamplifier into the ASC1's analog inputs. That way, I had access to and could digitize (for sonic better or worse) the three turntables and three phono preamplifiers currently connected to my system.

With the help of John Stronczer, Bel Canto's CEO and Chief of Design, I set up an Ethernet hub, and connected to it the Ethernet cable from the hard drive of my Meridian Digital Media System (formerly the Sooloos) and one from my MacBook Air laptop. We then ran Ethernet cables from the hub to the Meridian's controller and to the ASC1.

I ran an S/PDIF cable from the Meridian to the ASC1 and an AES/EBU cable from the Simaudio Moon Evolution 650D CD transport-DAC, to have access to its transport.

After downloading the JRiver Media Center app to my iPhone (I already had it on my MacBook Air), I had, from my listening chair, access to hundreds of high-resolution files on an external hard drive connected to the computer, almost 3000 CDs and hi-rez files on the Meridian—and, now that Tidal is implemented on the Meridian, access to everything streamable at CD resolution from Tidal. And, of course, I can get up and play LPs from my choice of three turntables—all of this adjustable, selectable, and switchable via three iPhone apps. My friends, that is music power!

Bel Canto Design, Ltd.
221 First Street N., Suite 300
Minneapolis, MN 55401
(612) 317-4550

JRT's picture

Bruno Putzeys' NCore variant of switch mode (class D) amplifiers, in combination with switch mode power supply, represents significant progress.

If well implemented, Putzey's NCore can be fully adequate for high quality audio, but that is not why it represents significant progress, because a well designed conventional class AB amplifier with conventional power supply can also produce high quality audio at similar power output.

What represents significant progress is that Bruno Putzeys' NCore variant of switch mode amplifiers, in combination with switch mode power supply, can also produce high quality audio at substantially reduced cost, reduced size, and with reduced power consumption, as compared to a conventional class AB amplifier capable of similarly high quality audio at similar power output.

I would suggest comparison of this Bel Canto MPS1 amplifier to a Parasound Halo JC1.

Here is a link to Stereophile's review of the JC1:

The Parasound Halo JC1 sells for less than $5K.

Bel Canto chose a $15K MSRP price point for this MPS1, and by doing that they have failed to deliver the real progress that Putzeys' NCore could and should provide.

Bel Canto's small dealer network in the US will sell a few of these, probably very few, and I suspect this Bel Canto product will soon fade into oblivion. I hope Putzeys' NCore does not fade as quickly.

JRT's picture

I'd like to see Bruno Putzeys' NCore implemented in active loudspeakers, with DSP crossovers, attached to a wired gigabit Ethernet network using Audinate Dante multicast. Dante uses conventional gigabit Ethernet switch and wiring.

The front end of the system could be as simple as a netbook running JRiver and Audinate Dante virtual soundcard. Dante virtual soundcard uses the wired Ethernet port to attach to a dedicated audio Ethernet network. The downstream end would be active loudspeakers, subwoofer(s), etc., also attached to the dedicated wired Ethernet network. In between would be nothing more than a conventional gigabit Ethernet switch and inexpensive cat5e wiring. That would eliminate a lot of the conventional resource hogs, and the majority of the system budget would reside in active loudspeakers. Setup and configuration could be extremely easy.

JRT's picture

A system using Dante could begin as a pair of loudspeakers (or even just one) attached to the network, and could be expanded by attaching new speakers to the network and adjusting settings on processing.

Audinate Dante over gigabit Ethernet can provide 16x16 24bit/192kHz (16 bi-directional channels), 32x32 at 24bit/96kHz.

edit: I should mention that I have no affiliation with any of these products or vendors.

JJSIII's picture

In response to JRT's comments, yes indeed nCore represents significant progress, the premium, customized 1200Watt capable module used in the MPS1 is NOT an inexpensive device. Also note that the MPS1 is MUCH MORE than a simple amplifier. Bel Canto has released a new e.One nCore based >500W mono power amp that retails for less than $5K a pair, the REF600M. It does not use the same nCore module as the MPS1 units but it does provide remarkable audio performance and value.