First Listen – HiFiMAN HM-901 high-resolution portable digital music player
Over the past year, the firm Astell & Kern has garnered considerable press attention, first for its AK100 high-res portable digital music player and then for its even higher-res AK120 player. The A & K players made a big splash and for good reason; their arrival in the marketplace was timely and the products offer exemplary fit, finish, and stylistic panache, plus user interfaces that—by all accounts—work very well. But long before A & K ever appeared on the scene the famous Chinese headphone/headphone amplifier company HiFiMAN had begun a multi-year-long development effort on an extremely ambitious high resolution digital music player of its own: the HM-901 ($999).
What makes the HM-901 so ambitious? Well, for starters the HM-901, which is all about delivering serious high-end sound quality, is based on dual ESS Sabre ES9018 32-bit DAC chips—units similar to those used in Oppo’s top of the line BDP-105EU universal player (and in many other even more costly high-end audio components). This certainly isn’t the least expensive way to go in preparing a high-res player, but HiFiMAN argues that it is the best-sounding way to go. In fact, company founder Dr. Fang Bian claims that in blind tests (at least one of which I’ve had the opportunity to observe) the HM-901 compares favourably with multi-thousand dollar/pound dedicated full-size DACs. The HM-901 supports 16-bit formats (mp3, flac, ape, aac, alac, aiff, and wav) as well as 24-bit formats (mp3, wav, flac, and alac), with decoding for up to 192/24-bit files.
Second, the HM-901 provides very high-performance, user replaceable amplifier modules, with different variations for different types of headphones and earphones. At present the firm offers three amp options: a Balanced-output Amplifier
Card, an IEM Amplifier Card, and a special “HM-901 Minibox Amplifier Card” designed, says HiFiMAN, by “renowned portable amplifier designer, Three Stone.” The point, here, is that HiFiMAN give you options, offering different amp modules tailored to fit specific applications—something no other portable player maker we know of has seen fit to do. Our evaluation unit came with the Balance Amplifier Card already installed and that is what we have been using thus far.
However, the sound-quality oriented feature set doesn’t end here, in that the HM-901 provides a precision stepped attenuator volume control, a balanced/single-ended output switch, high & low gain setting controls, an HD/Vintage DAC response-shaping control switch and can—at the user’s option—be fed directly from an S/PDIF input. Most of the time, though, we imagine users will instead choose to run the HM-901 directly from its onboard SD card, which of course means owners can buy as much or as little digital file storage capacity as they desire. The player ships with a power charger, a 1600 mAh lithium-ion battery, a USB to multi-pin adapter cable (used in downloading music files from a PC to the HM-901’s SD card, and a combo S/PDIF input/RCA line-level output cable that facilitates use of the HM-901 as a traditional high-performance DAC.
In the relatively near term, HiFiMAN also plans to release a tabletop DAC/dock for the HM-901, where the idea would be to have the dock permanently connected to one’s full size hi-fi system and to plug the HM-901 into the dock for in-home use but to unplug and carry it along for the on-the-go listening. Where most portable players are geared almost exclusively for on-the-go use, HiFiMAN plainly envisioned a much more extensive set of possible “use cases” for the HM-901.
How does the HM-901 sound? I will have to proceed with caution, here, as I have learned that, quite by accident, HiFiMAN shipped us an HM-901 sample whose firmware was several revision levels out of date. Since at least one of the intermediate firmware revs had addressed a firmware updating issue, both the HiFiMAN team and I felt it would be best to get a sample with the latest revision software before contemplating a full review. Nevertheless, I can give you some off-the-cuff impressions of the HM-901 as run with down-rev firmware.
From the outset, it seemed to me the HM-901 wore its “high resolution” credentials on its sleeve, offering up a notably clear, crisp, and well-detailed presentation on the music files I tried (I used a mix of 44.1/16, 94/24, and 192/24 wav files for my initial listening). While I would not call the sound overtly bright in any way, it is a sound that definitely does not add even subliminal touches of warmth (which some of HiFiMAN’s larger desktop amplifiers tend to do). Thus, the HM-901 arguably qualifies as a higher accuracy component that offers a superior degree of neutrality and transparency, albeit at the expense of touches of comfortable warmth that some headphone listeners might find appealing. As I gain more experience with HiFiMAN’s available amplifier modules and with up-to-date firmware, I’ll no doubt have more to say about the unit’s sound. For now, though, let’s just say that first impressions seem promising.
One element of the HM-901 that tends to be a bit polarizing would be the player’s styling, which is sort of a 21st century, retro-modern take on the look of a vintage Sony Walkman. In this, you can see a deliberate homage to HiFiMAN’s very earliest days, where the company got its start by building what were in essence hot-rodded version of the then ubiquitous Sony players. Will you appreciate the HM-901’s look? Well, if you heft the unit in your hand, you can’t help but appreciate the beefiness and solidity of its build quality. On the other hand, if you put it alongside an Astell & Kern AK120, 10 out of 10 hypothetical viewers would probably pick the A & K as by far the more modern design. As one office mate put it, “The HiFiMAN is a strange unit, because its sound is modern as tomorrow while its appearance is definitely old-school.” You be the judge.
Watch for a possible Hi-Fi+ review of the HM-901 later in the year. Until then, happy listening and a happy 2014.