Media Server Reviews

It's time to fulfill my promise to write about Playback Designs' Sonoma Syrah music server and Sonoma Merlot DAC. It all began when I asked Playback's founder and CEO, engineer Andreas Koch, when he plans to produce a multichannel digital-to-analog converter—a question I've put to so many other manufacturers. He said that he already had a multichannel system on the drawing board, and not just a DAC. Our e-mail exchange culminated in his announcement of the Playback Designs USB-XIII Digital Interface, to be used between a USB source component and as many as three DACs via PLink, Playback's proprietary fiber-optic connection.

It's been going on for a while now: Despite support for multichannel in audio/video receivers and A/V processors priced from as little as $200 to $30,000, there are still very few offerings that cater to the music listener. They may offer stereo-only streaming features through their USB or Ethernet inputs, but these inputs don't see your multichannel files. To handle such files, they would require you to add a music server with HDMI output. However, I know of no turnkey music servers that will output multichannel audio via HDMI.

When I reviewed the Antipodes DX Reference in October 2015, that $7500 media server made musical mincemeat of my regular computer audio setup: a headless 2.7GHz i7 Mac mini fitted with 8GB of RAM and Pure Music and Audirvana apps. Coincident with the publication of that review, Aurender launched its N10 music server ($7999) at the 2015 Rocky Mountain Audio Fest. I had been impressed with Aurender's Flow USB headphone amplifier when I reviewed it in June 2015, so I asked for an N10.

The 2015 T.H.E. Show in Southern California clashed with my having to be in the office to ship our August issue to the printer, so I wasn't able to attend. But in devouring the online coverage on www.stereophile.com and its sister sites, on InnerFidelity.com I found a report by Tyll Hertsens about two new hi-rez portable players that made their debuts at T.H.E. Show: Questyle Audio Technology's QP1 ($599) and QP1R ($899).

Perhaps because I grew up in post-WWII England, with austerity and food rationing the norm, I learned at an early age the value of frugality. It was a financial stretch for me to buy, in the late 1960s, my first real audio system: Garrard SP25 turntable with Audio-Technica cartridge, Kenwood integrated amplifier, Wharfedale Super Linton speakers. Even when I could afford to upgrade the system, other than replacing the Garrard with a Thorens TD 150 and the Audio-Technica with a Shure, I went the DIY route. Back then, in the early '70s, I assumed that the advent of op-amp chips like the Fairchild Semiconductor µA741 would make it possible for me to design and make, for example, a good-sounding preamplifier for a lot less than it cost to buy one from an established manufacturer. That assumption turned out to be wrong, of course, but frugality was, by then, a habit: too ingrained for me to shake entirely.

Do you travel? Commute, perhaps? Just like to listen to music privately around the house? No matter—the Astell&Kern AK240 is the luxury choice in high-resolution portable music players (footnote 1). It even comes with a lovely leather case that beautifully cradles its angular beauty. The AK240 can play all of your PCM files, up to a resolution of 24-bit/192kHz, as well as DXD and single- and double-rate DSD, natively, and can do so from its internal storage, from a microSD card, or from your computer via WiFi or a wired connection. It can also function as a DAC or USB-to-TosLink converter. I'm not so sure there's much left wanting.

Power amplifiers are unglamorous but essential. In theory, they have only one task. But, according to audio sage Yogi Berra, "in theory, theory and practice are the same. In practice, they are not." Amplifiers must take a voltage input signal and provide an output of somewhat higher voltage but of substantially higher current, the product of which is power. The task is complex in that this output must be applied to electrical interfaces whose characteristics vary widely from speaker to speaker—across the audioband and, for some, even at different power levels. There are no control mechanisms or feedback signals to help. The power amp must just stand and deliver.