A Survey of Digital Audio Players Part 1 HiFiMAN HM-802


HiFiMAN HM-802
Most headphone aficionados these days know HiFiMAN for their planar magnetic full size headphones. That seems to be the main focus now, along with a supporting cast of desktop amplifiers. But veterans in the headphone game probably still think of the firm as an IEM company, as that was their main focus in the years before the planar magnetic revolution. HiFiMAN was also one of the few companies making expensive DAPs, until this new wave came along. Their HM-801 was popular in 2010 when practically zero competition existed in the premium category.

While not exactly receiving the same attention as the planar magnetic headphones, HiFiMAN's DAP line has steadily evolved over the past few years. This culminated in the $999 HM-901 which remains the current top model (until the upcoming 901S officially launches in the USA). That thing has been reviewed many times over the past few years so I chose to cover its little brother, the more recently released HM-802 ($699). The 802 received very little attention for some reason, despite being a very similar product in almost every way...for a lot less money. After comparing the two directly, I may actually prefer the cheaper sibling, so it's definitely not something to overlook merely for being in "second place".

External Design
The HM-802, at first glance, looks like it might be a Tascam field recorder. You know those sleek lines from the AK240? The modern look of the Calyx? You won't find any of that here. The HM-802 is unapologetically bulky. It's got an old-school vibe to it, but not in a hip, retro way. Build is mainly plastic and feels a little cheap at times—the battery cover is especially obvious. But the boxy look and 250 gram weight (the heaviest in this comparison) somehow counteract the plastic feel by making the device seem virtually indestructible.

As you can see in the pictures, the 802 has a rather busy design. We get a grand total of 6 switches, 6 buttons, and two spinning things with which to control various aspects of the player. That maybe sounds more complex than it really is, but let's be clear—this thing doesn't possess even a fraction of the grace found in the Astell&Kern models.


Size comparison between the HM-802 (bottom) and Calix M (top).

Internal Design
The HM-802 is essentially the same as HiFiMAN's HM-901 but with dual mono Wolfson WM8740 DACs used in place of the 901's dual ESS chips. They also redid the output stage, optimizing for the unique requirements of the different chips. Everything else remains, same stepped-attenuator based analog volume control, same gain options, same battery, etc. The "Wolfson sound" is stereotypically thought of as being warmish while the "Sabre sound" is more lit up. I don't put much stock in these universal generalizations though at times they do happen to line up with reality.

By far the most interesting aspect of the device is its modular nature. Remove the battery and you'll see the amplifier "card" which can easily be swapped out for another. HiFiMAN has several different cards available which focus on different things: one for balanced mode, one dedicated to IEMs, etc. This means the device can be tailored to a particular need more so than other DAPs which lack this modular design. It's worth noting that more amp options exist in HiFiMAN's home market—I've even seen some hobbyists design their own cards. The choices available for us in the USA are somewhat more limited, though an enterprising 802 user could eventually track down more cards if they really worked at it.

The 802 supports hi-res PCM up to 24-bit/192kHz. It supposedly handles DSD, limited to DSD64 in the DFF format. I was successfully able to play DSD tracks using an older firmware, but when I updated to the latest it no longer works—I mainly hear static. I also get static playing 24-bit/176.4kHz material. To be fair, that (rather uncommon) sample rate has caused issues in the past with other gear.

User Interface
HiFiMAN calls their UI "Tai Chi", ostensibly meant to suggest smooth, flowing operation. I see what they were going for but frankly I don't think it worked quite as well as they intended. The UI is serviceable but nothing more. With the exception of Fiio's X5, every other DAP here has an edge over the 802.

A large portion of my complaint is actually centered around the scroll wheel, which is just not very responsive. As with the X5, it seems like a solution waiting for a problem. A simple 4-way button system would seem a better choice. If they were dead-set on keeping the wheel for some reason, it would need a better feel to it—both the surface of the wheel and the way it acts in the menu. As it stands I end up spinning the wheel and never being confident I'll see a corresponding action on the menu. The wheel is physically slippery despite having several "ribs" for grip. And it seems too stiff—I thought it might break in a bit after use, but so far no change.

Aside from that, the UI is attractive enough if fairly basic. HiFiMAN has a demo available here allowing you to see navigation and playback. As you can see, it's a fairly straight forward UI that gets a slight boost from little animations and such—but it's still nothing too amazing.

HiFiMAN made some interesting choices here. On the plus side, we get a full size SD card slot, which means higher capacity cards for lower prices than their microSD counterparts. This is welcome since the device has no built-in memory of its own. We also get the option of balanced output when using HiFiMAN's balanced amp card—it uses a 3.5mm combo jack which also works with standard unbalanced headphones. This is different from the A&K DAPs which use a separate 2.5mm jack for balanced mode. Lastly, a bundled adapter provides analog RCA outputs and a digital (SPDIF) input connection, for using the 802 as an outboard DAC.

On the flip side, there are some negatives here, chief among them being HiFiMAN's choice of a proprietary connection jack. This means dedicated cables are required for charging, data transfer, and anything else that might interface with the device. Since most others use standardized microUSB, this is a minor annoyance. Also note a complete lack of any wireless connectivity—which may or may not matter to you.

HiFiMAN does have a noteworthy accessory called the Dock-1. It's a substantial desktop dock which costs $499 and adds significant functionality. This device has made appearances at shows going back several years, and is one of the reasons I wanted to try out the 901 when it first came out. It finally became available and, while expensive, looks like a very useful device. It boosts the line output level to as much as 3 Vrms, adds a host of inputs and outputs, adds a remote control.... this effectively turns your DAP into a legit source for desktop use. Oh, and it looks great in the process. If this sort of thing is to your taste, it could really set the HiFiMAN units apart from their competitors.

The HM-802 lasts roughly 10 hours which is midpack in this roundup—it's not amazing, nor is it terrible. It seems to be fairly consistent in that playing high-res tracks or driving more power-hungry cans doesn't drain the battery much more quickly, compared to playing CD quality tracks via IEMs. Other DAPs show more variation in that regard.

Sound Quality
The HM-802 is a very enjoyable player. All my gripes about the controls and the UI seem to fade once I hear the lush, velvety presentation. It's not terribly dissimilar from the Calyx M in some ways—both have somewhat relaxed top ends which don't seem to suffer a lack of detail, but rather present things in an effortless, fatigue free manner. Where they differ is that the 802 is even more relaxed, even warmer, with a sweetness of note that screams "analog" even more loudly—for better or worse. If the Calyx is a classic Parasound DAC (to follow the analogy I used prior), the HM-802 brings to mind the Audio Note DACs and CD players. Those models (not cheap!) used older DAC chips such as the Philips TDA1543, the Analog Devices AD1865, or the TI PCM63, and are known for their rich tonality.

The resulting sound is something I usually find compelling, though I can see how it might not be appealing for others. It doesn't have the sparkle some people love, and when paired with a darker headphone the sound is a bit muffled and closed in. Those seeking a more neutral, linear presentation should look elsewhere—perhaps consider the HM-901 which sounds more lit up and resolving but to my ears less musically pleasing, again depending on the situation.

Of course, that warm tone of the 802 is just a baseline, and the final result will be determined by your chosen amp card. $699 gets you the standard amp module based around an Analog Devices AD8397 opamp. With a 1 ohm output impedance and a max output of 150mW in high gain mode, the standard card is a good all around performer. It can sound a little constricted at times, and tends to lose the plot with complex material, but aside from that I'm pleased with its performance.

HiFiMAN also sent along an IEM card and a balanced card, both of which improve performance even further. The IEM card ($229) uses a pair of OPA627 opamps each driving an OPA634 buffer. Output impedance is 2 ohms which is acceptable for all but a few IEMs. The low gain setting tops out at 1v and 33mW which might sound inadequate for big headphones but is perfect for IEMs. The resulting noise floor is exceedingly low. High gain mode delivers 1.4v and 65mW making it suitable for more than just IEMs, but it still can't handle tough loads. The sound signature of the IEM card is a bit more neutral than the stock amp—it's got superior resolution and doesn't sound muffled as the stock card sometimes can. It also does a lot better with orchestral works and other complex material. To my ears, the 802 with IEM card is up there with the Calyx M and AK240—but only when listening with IEMs or other easy to drive cans.

The balanced card ($299) is very similar to the IEM card but doubles everything—so quad opamps and buffers. It's basically two of the IEM cards combined onto a single PCB. In low gain mode, using a standard unbalanced headphone, the output is nearly identical to the IEM card—which makes sense, as it only uses "half" of the amp in that configuration. Using a headphone terminated with a balanced TRRS plug, flip the switch to balanced mode and enjoy the full potential of this amp card. Balanced mode on the high gain setting pushes a very impressive 477mW and swings nearly 4 volts, making it potent enough to drive most full sized cans with authority. It's characteristics are very similar to the IEM card—top end clarity is significantly improved over the stock amp card, and soundstage is quite a bit more expansive and layered. The only downside? The TRRS termination is not all that common. HiFiMAN's RE600 IEMs use it, and those sound great using the low gain setting, but all that extra power isn't really necessary. Aside from that IEM you'll need adapters to make the most of other balanced headphones. If you need the power though, the balanced card may be just the ticket.

castleofargh's picture

cool to see something about DAPs.
I usually whine a lot when reading reviews as they always are too nice with the devices, forgetting to tell about the shameful side of a device. well I must say, this time the practical reports felt spot on for the stuff I own or could try(and I really don't say that often).

I also wondered about the hm802 not getting much love. it's too big for me, I'd rather have smaller and use an amp when necessary, but it seemed like a pretty good product.

John Grandberg's picture
If everyone writes fawning reviews and leaves out all the disappointing aspects, how will the companies making these DAPs ever learn?
Dopaminer's picture

Great review so far; really looking forward to Part II. I think you should reconsider your iBasso stance and include the DX90. Judging by the headfi threads, the DX50 and DX90 have been the `gateway` daps for many audiophiles who transitioned from smart phones or ipods, and then subsequently `moved up` to higher priced (sometimes MUCH higher priced) daps like AK240, etc. The DX50 and DX90 are highly relevant in any comparison, especially the DX90 with its power and dual sabre dacs, and its huge following.

John Grandberg's picture
I have to admit, I'm still sore at iBasso for blowing out my $750 set of CIEMs with their stupid volume bug. You're totally right about their relevance, but I'm just not sure I'm "there" yet.
tony's picture

Thank you for explaining the differences in all these players.

I'm reading and trying to imagine each player vs. my iMac/Schiit system.

Does anyone offer an iMac in shirt pocket size?

Anyway, nice bit of work here.

Tyll, Joker, Katz and Grandberg make a pretty strong group of journalists.

Tony in Michigan

potterpastor's picture

Tremendous survey so far! I love my Sansa Clip and my Sansa Clip+. By the way, I prefer the sound quality of the original Sansa Clip over the 2nd gen Sansa Clip +, but the original clip doesn't have a slot for micro sd cards.

John Grandberg's picture
I haven't had an original Clip in ages. No memory expansion = no go for me. But it's interesting that you like it more for SQ. I know they switched to a newer AMS SoC for the Clip+ and newer models, so I can see how it might be a little different. Personally I recall them sounding the same but I can't say I spent a lot of time comparing.
potterpastor's picture

The Sansa clip firmware is really sluggish and slow. It takes hours and hours to refresh the media every time you intentionally or accidentally move the microSD card. It is just not feasible.

You didn't review the iPod touch fifth-generation, but it probably is the best of all the players. It is so easy and fast to load music, and it sounds great.

Impulse's picture

I've been using a Clip Zip for running for a few years now, along with a pair of MEElec M6. Tempted to swap them for my Xiaomi Pistons but I like the fit of the M6 a lot when it comes to being active.

I used to take along the Zip when traveling but my Nexus 5 doesn't really burn thru battery much while playing music. I'm usually sending it via Bluetooth anyway to a Sony MW600 receiver (and my V-Moda XS or Ety IEM).

That's one category of devices I'd love you guys to survey, ClieOS tested some of the Sony/Samsung BT receivers on Head-Fi a while ago but it was not an exhaustive review. I feel like they kill two birds with one stone...

It takes the burden of output (DAC and amplification) off your phone or tablet, while also cutting down on wires, particularly when used with something like the XS with removable cables you can swap for short ones.

Impulse's picture

A BT receiver lets you enjoy the headphones you already have with a minimum of wires without getting pricey dedicated BT cans or a compromised set...

It's not something I use at home, at all, because I know BT is ultimately a bottleneck to what my cans are capable of (never mind my Asgard 2); but it's ultra convenient on the go...

As much as Tyll complains about how cramming batteries and BT electronics into a pair of cans tends to hurt their design you'd think these things would've come up in the conversation a few times.

John Grandberg's picture
I have a Noble BTS on the way, hoping it accomplishes just what you mention. From a design perspective it looks like just what the doctor ordered for a smartphone with high output impedance or just generally lazy sound quality. We'll see.
Impulse's picture

Looks kinda pricey compared to some of Sony's BT receivers with comparable battery life AND a display for track info, caller ID, etc... But if the sound quality is a cut above the rest it might very well be worth a look.

I'm definitely looking forward to your take on it. I don't particularly need the display on my Sony anymore since my smart watch accomplishes the same function. Being BT 4.0 that Noble unit might get better battery life than advertised with BT4.0 compatible phones.

I've heard great AptX BT devices as well as awful ones, not putting much stock that, the standard SBC codec seems decent enough if a device uses the highest bitrate... I've wondered whether AptX is more efficient but, no one tests for that kinda thing.

John Grandberg's picture

We'll see. The sub-1 ohm output impedance is promising. You don't typically see that spec on gear from other brands.

Which Sony model do you use?

Impulse's picture

I'm using a Sony MW600, pretty old unit, I think it's discontinued now but still widely available at close to it's original price. I believe they replaced it with the MW1 but that seems discounted too, not sure if the SBH5x models are their most current or what.

I get pretty good battery life out of it tho (over 7hrs still after a few years), I remember comparing it to my Clip Zip with my Ety hf3 but it's been a while... Now I'm curious to do so again.

Ended up settling on it basically based off Amazon reviews, a couple positive comments about it or the MW1 on Head-Fi, and just the fact that it looked better than a similar unit by LG. It's hard to find detailed specs like output impedance or DAC used, much less anyone that has more than one of these things for comparative purposes.

ManiaC's picture

Please if you can add Cayin N6 and Fiio X3 2-nd generation.

John Grandberg's picture
I have the Cayin N6 here now, as well as QLS QA360. Both are worth talking about. Should be able to get the Consonance Suzanne as well, but I'm not sure if the Questyle QP1 will be done in time.
Tyll Hertsens's picture
Yeah, but by the time the Questyle comes out you'll have a lot of great experience to evaluate it with. Thanks, John, great work here.
tony's picture

Another Wiki type of reference work.

You guys keep hitting home runs.

This portable comparison is doing Tons of work for me and probably for everyone else.

I'd buy a plane ticket to see a Seminar with all four of you lads.

You 4 are becoming a "Top Gear" type of experience, you might be able to do a weekly show ( remote kind of thing, like that TV guy does ). Betcha you'd be getting a huge following.

Tony in Michigan

elfary's picture

iPhone 6 output impedance is 2.3 ohms. Check your facts (or measurements).

tony's picture

Nice catch here elfary,

Tony in Michigan

John Grandberg's picture
And so did Ken Rockwell on his site. He got 3.18 ohms on the 6+, and I got a bit higher than that. Within margin of error/unit to unit variability I suppose. The point stands that it's pretty good as-is, but not perfect - there is some improvement to be found with a lower output impedance, when using certain IEMs.
Stefraki's picture

Have been increasingly falling in love with my Pono. Functionally speaking, it's very silly in several aspects... sound quality-to-price ratio? It's amazing.

John Grandberg's picture
Pono will be included in Part 2.
ednaz's picture

It's difficult in these online shopping days to do good research on your own. When I decided I wanted to step up from the iDevices, I couldn't find anyplace where I could listen to 2 or 3 alternatives with the IEMs and headphones I own. As fraught with argument as an exercise like this can be, it's a necessary tool (unless someone wants to order four or five units and sell off the ones they don't like.)

I agree on your assessment of the Fiio X5 sound, that's agreement from someone who enjoys listening to the device. But I think it's a problem with some earphones, but not at all with others. With my Westone ES5, it's edgy metallic for sure. But with other earphones or headphones - Xiaomi Piston 2, Ety custom sleeved, ACS T1 CIEMs, my AKG Quincy Jones portable headphones - it's not noticeable at all.

That's where the YMMV comes in - really seems to me that in a lot of cases you need to look at DAP/headphone combinations. Which makes for a combinatorial nightmare. Still, with good roundup reviews like this, and knowledge of your own headphones, it's possible to get to happy.

Three Toes of Fury's picture

I absolutely enjoyed this first collective look at DAPs.
Thank you very much John for compiling your thoughts and sharing them with the innerfidelity gang.

I share @ManiaC's interest in the Fiio X3ii as its been getting some pretty great buzz on other audio sites. However im guessing its sound quality wouldnt exceed the X5 and we have your review for that one.

Keep up the great work and keep sharing your thoughts and reviews. We headphone fans love our electronic toys..having more DAP reviews and wall-o-fame entries are a perfect fit for this site!

Peace .n. Living in Stereo


PS: What about adding Zunes, Archos Jukeboxes, Creative NOMADs, Diamond Rios, or the audiophile-standard-setting coby usb player!?

tnelson's picture

I'd be interested to know more about the target users of dedicated DAPs with higher SQ than iPhones and other smartphones. I honestly am curious about this issue…I understand wanting the best possible source for an environment in which you can discern SQ clearly and maybe wanting a physically small personal source that can be moved from quiet listening site to site (home, office, etc).

However, I am skeptical that benefits of a high-SQ DAP can be heard if used as a portable player. On streets, planes, cars, in coffee shops…there's no way I'd be able to hear an enhancement beyond my iPhone, regardless of how good the source or IEMs. Too much isolation or noise-cancellation can be dangerous on the street, so there's always going to be ambient noise.

I would still need my phone for streaming (or lossless downloaded) TIDAL, internet radio, plus all the non-audio smartphone functions. Why carry another device? It would be interesting to evaluate a current iPhone and Android phone among the DAPs being compared for SQ, for folks like me who are skeptical about the audible benefits of carrying a second audio device. Doesn't fit my lifestyle, but what is the target listening market for these?

John Grandberg's picture
I definitely agree that any benefit is lost in a noisy environment. That almost goes without saying. But each situation is different - two people commuting to work might have vastly different ambient noise situations. One might not be a good candidate for anything beyond a phone and decent IEMs, the other might be well served by a nice DAP and higher-end IEM. So you have to examine your own scenario and go from there.
On Song Audio's picture

Hi I am the U.S. representative for the M. Please keep in mind that the M can play while plugged into a 5 volt USB supply. The 4 to 5 hour battery life applies when a power outlet is not within reach.

Laistrogian's picture

I'm wondering if it's possible to do measurement for these DAPs. While I can understand why some people would want to by DAPs, something like A&K240 comes across me as being "unnecessary."

You could call me objectivist or something like that but for me it's still physics, if the numbers are the same they should sound the same.

SixChannel's picture

2 years ago I settled on a Samsung Galaxy because it 1)has a true FM radio, 2)has open architecture for music player and 3)allows me to peruse the innumerable internet stations. Although I see FM a lesser draw these days, opening up to the internet swung the deal for me. The only unfortunate part is that the amplifying stage isn't the best for my big cans, but I fixed it by strapping it to an amp.