Digital Processor Reviews

I eat bits for breakfast. Lunch is a simple bit-sized snack. And dinner is the analog to real food. This has been my routine these past four years as editor of AudioStream.com, where we digest all things computer audio.

In that time I've reviewed over 100 digital-to-analog converters, ranging in price from $60 to over $12,000. This adds up to roughly 150,000 words spilled on DACs. You'd think my pen would be running dry—especially if you feel, as some do, that all DACs sound pretty much the same. If that were the case, I could have written just one review, for that very first DAC, then cut and pasted it for all the rest. What was I thinking?

I was alerted to the new VEGA D/A processor from Chinese manufacturer AURALiC by Michael Lavorgna's rave review for our sister site AudioStream.com in April 2013: "Everything I played through the Auralic Vega was equally wow-inducing. Everything. . . . Music I've heard hundreds of times was presented with a crisp, clean, and delicate clarity that was simply uncanny and made things old, new again. . . . Its ability to turn music reproduction into an engaging and thrilling musical experience is simply stunning."

Aurender was a name new to me when I encountered the company at the 2015 Consumer Electronics Show, where they displayed a range of music servers designed in California and manufactured in South Korea. But what caught my attention in Aurender's suite was their Flow portable D/A headphone amplifier ($1295). This handsome, battery-powered device, housed in a machined aluminum case about twice the size of a pack of playing cards, offers optical S/PDIF and USB 2.0/3.0 input ports and a single ¼" stereo headphone jack. Two features distinguish the Flow from the pack: Its USB input can be used with iOS (iPhone/iPad) and Android smartphone sources, and it can accept an mSATA drive (not included in price) of up to 1TB capacity for internal storage of audio files. Visually, the Flow's distinguishing feature is its round LCD display, which stands proud of the faceplate; the bezel encircling the display acts as a velocity-sensitive volume control operating in 0.5dB steps.

I first spied the Ayre Codex two Januarys ago, at the 2015 Consumer Electronics Show, and its scrappy proletarian vibe sure made it look different from any other Ayre creation. On learning that its price would be well under $2000, I was immediately curious what Charley Hansen and his gang—makers of the $3450 QB-9^DSD USB digital-to-analog converter, plus a few five-figure amps and preamps—could create when cost is an object.

These days, it seems you can't shake a stick without hitting a USB DAC, but Ayre's QB-9 ($2500) is something a little different. Ayre's marketing manager, Steve Silberman, was adamant: "The QB-9 isn't a computer peripheral. It makes computers real high-end music sources."

John Stronczer, Bel Canto Design's technical spark plug, meets my definition of an electronics renaissance man, ranging as he does from designing single-ended amps that glow in the dark (the Orfeo) to digital processors (the Aida). Actually, digital circuitry is one of John's specialties, dating back to his days at Honeywell.

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."