The technical performance of the MPS 1 monos doesn’t play second fiddle. Their SN/R at the speaker terminals is given as an astonshing 128dB! They deliver a substantial 300w/8Ω which doubles into 4/2Ω respectively to generate 1.2KW into low impedance. There's 40 amperes of peak current, sufficient for just about any speaker imaginable. Digital signal departs the ASC1 via ST optical glass fibre to be reclocked inside the MPS1 with internal <35 femto-second master clocks before being finally converted via Burr Brown PCM1792 converters operating in double-balanced mono. Claimed distortion for this D/A conversion stage is another exceptional 0.0005% with 130dB of dynamic range.


After passing Bel Canto’s discrete I/V and voltage gain stages, the balanced analog signal drives a sophisticated output stage based on Bruno Putzeys’ well regarded nCore class D modules customized for Stronczer for low gain to guarantee top dynamic range [this also cleverly minimizes attenuation requirements in the digital domain – Ed]. Again, this power buffer can deliver 40 amperes and in excess of a kilowatt into a 2Ω load, all with vanishingly low output impedance to make it quintessentially transparent. The power stage uses four high-voltage Mosfets in alternating operation. At the rear, the latest generation of WBT NextGen speaker terminals are isolated from the chassis and cabled with a custom-manufactured Kimber harness. Feeding each MPS1 monaural amp are unique hybrid multi-stage power supplies. This architecture incorporates an AC power conditioner designed specifically for Bel Canto Black which precedes a switching power supply for the high-voltage section, linear regulated power supplies for small signal analog stages and separate regulators for the digital circuits. When you consider this setup which applies D/A conversion just before the final output stage and handles signal transfer between controller and power amps in the digital domain, John Stronczer has radically shortened the signal path in the analog domain and done so with total isolation of the left/right channels.


All three Black components are housed in stunning black-anodized aluminium billet machined chassis with constrained layer damping to provide a quiet environment free from external interference and vibration. Each digital audio stage is confined to its own internal bay to not interfere with other circuits. Conical Delrin feet optimize stability and provide further mechanical isolation. StreamLink connectors were deemed most effective to isolate the monos from external electromagnetic interference. The fiber-optic ST leads were developed for greatest transfer speed and lowest noise. Their robust performance allows positioning of the three components without any distance constraints since these cables are immune to all forms of EMI, RF and ground loops.


On the software side, Bel Canto as yet haven’t authored a dedicated app to control their renderer. The only available app download is for the remote control of the ASC1. There is little need though to exchange the standard machined IR remote control for its iOS version since the display remains of exemplary clarity at over 3 metres. This is not the case for most the competition. It probably was one of the few times I didn’t have to squint to read a display or walk up to it. From the distance, you can duplicate the functions of the hardware control wheel, i.e. alter volume, balance, inputs, filters, phase and gain although the iOS app has a useful page for secondary functions such as turning specific inputs on/off or renaming the inputs with up to four alphanumeric characters.


For control of your library and playlists, you must use a third-party app either via computer or a UPnP control point running Android or iOS. John Stronczer recommends JRiver and JRemote. This requires running a computer for JRiver that’s connected to your network. A computer would also be used to perform software updates for the ASC1 or its internal media renderer using a web page on the renderer preset for future updates to either device. There are alternatives to a UPnP control point with a number of options for Android or IOS. The problem is poor standardization of DLNA/UPnP protocols such that communications and management of playlists can often be chaotic. Bel Canto Black is not immune to these problems and many apps I tested with their ASC1 renderer proved quite ineffective, especially Kinsky, MPD and SongBook Lite. Most robust of those was the one developed by German manufacturer Audionet which still was necessarily constrained when used with a competing brand. It’s a pity that ergonomics haven’t been pushed farther to harness the full power of Minimserver which in its latest version is just as powerful as JRiver but would require changing the ASC1’s protocol to the UPnP Open Home standard. This protocol is used by Linn and Lumin and exploits the power of Linux-based servers with 3rd-party apps without facing any playlist issues (like Lumin’s for example which is now used by a good number of Linn owners).