Media Server Reviews

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).

Questyle was a name new to me. The company, based in China, has its products manufactured by Foxconn, of iPhone fame, but its North American operation is headed up by Bruce Ball, a veteran of the high-end audio industry. The two new players are very similar, differing in internal storage capacity—the QP1 has 16GB, the QP1R 32GB—and, according to Questyle, the QP1R uses higher-quality components and different firmware, and offers lower distortion and superior sound quality.

As much as I love the sound of the Pono Music PonoPlayer that I bought to replace the Astell&Kern AK100 on my daily commute, its Toblerone size and shape mean that it won't fit in my shirt pocket—and in New York City's summer swelter, I don't wear a jacket with a pocket into which I can slip it. The slim Questyle players looked tempting. I felt I should review the affordable QP1, but my baser instincts got the better of me—I asked for a sample of . . .

The QP1R
The size of a pack of cigarettes, the QP1R is housed in a CNC-machined aluminum chassis with a gray or a gold anodized finish. The front and rear panels are made from iPhone-esque Gorilla Glass, the front dominated by a square, color LCD screen and metal scroll wheel. This wheel has a central pushbutton and, around its circumference, four touchbuttons; a button on the QP1R's right edge acts as both the On/Off switch (long push) and disables/enables the control wheel, buttons, and the displays (short push).

The wheel's central button acts a Play/Pause control as well as a Select button, while the four other buttons—labeled Home, Return, Right, and Left—allow the settings menus and music library to be navigated in conjunction with the scroll wheel.

On the QP1R's top edge are two 3.5mm jacks. The left-hand jack is for headphones, the right-hand one for both analog (line level) and digital (optical S/PDIF) outputs. The line output can be set for fixed or variable level. To the right of the jacks is a conventional rotary volume control, protected by extensions of the aluminum frame. As supplied, there were two choices for maximum gain, High and Low, but with the latest firmware (HW v.4 and SW v.1.02), released during the review period, there are now three gain settings, to allow the player's output be optimized for specific headphones. The output impedance is specified as 0.15 ohm, which means the QP1R should have no problem driving even low-impedance in-ear monitors. The latest firmware also implements two independent octave-band graphic equalizers. As these offer up to ±6dB of adjustment, activating each drops the overall volume by 6dB, to avoid digital clipping.

The player's base has a micro-USB port flanked by two slots, each of which will accept a microSD card of up to 128GB capacity, for a maximum storage of 288GB. Questyle recommends FAT32-formatted cards, but I had no problems with an exFAT-formatted 64GB card. The micro-USB port allows the QP1R's 3300mAh lithium-polymer battery to be charged by a host computer (no AC adapter is supplied). Charging is said to take eight hours from a USB port.

The QP1R supports the regular PCM file formats—ALAC, APE, FLAC, AIFF, WAV, WMA Lossless—up to 24 bits and 192kHz. It also supports both DSD64 and DSD128 files, in DFF and DSF formats. The DAC chip is a Cirrus Logic CS4398, which features a combined multibit delta-sigma architecture operating up to 192kHz. The CS4398 handles DSD data natively, according to its datasheet, and is the same chip used in Astell&Kern's well-regarded AK240 portable media player.

Questyle says that the QP1R has three voltage-stabilized power stages, and that its headphone amplifier features a patented current-mode topology with discrete devices biased into class-A. (The player did get warm after playing continually for an hour or so.) Operating in current mode is said to offer low noise and very wide closed-loop bandwidth, even after the application of negative feedback. Having learned my electrical engineering in The Age of Tubes, which are voltage-mode devices, I have never been able to get my head around current-mode circuits, so I will have to take Questyle's claims on trust. It's what it sounds like that matters.

Use
Loading both the QP1R's internal memory and the microSD cards is a simple matter of connecting the player to a host computer and drag'n'dropping the audio files onto the respective desktop icons. When the icons are ejected in the usual manner and the USB connection is broken, the player automatically scans its storage and rebuilds its music library. (There is also a manual option for doing this.)

Questyle claims a battery life of up to 10 hours, which seemed about right. The QP1R has a tactile feedback feature that I found invaluable: Whenever one of its buttons is pushed, the player vibrates briefly. However, I had some problems with both the scroll wheel and the touchbuttons. Using the QP1R in the office, with it lying on the desk next to my keyboard, the wheel and buttons would respond only intermittently. I found I had to hold the player to get consistent operation. But I loved the multilevel Return button, which got me quickly back to the Now Playing screen after I'd been adjusting, say, the equalizer settings.

Listening
I found the QP1R's graphic equalizer useful with the AudioQuest NightHawk headphones, which Herb Reichert reviews in this issue's "Gramophone Dreams" column. To sound neutral, these 'phones benefited from a slight, +2dB boost at 8Hz and above, and an equally slight cut at 62Hz and below. My Audeze LCD-X and Ultimate Ears 18 Pro headphones were okay with the Questyle's equalizer disabled, however. The following comments are an amalgam of my experience with all three headphones.