HIFIMAN HM901s Portable Music Player Review

Equipment used:

Headphones: RHA T20, AKG K7XX, LCD-2f, RE-400, HD-650, HE-560

Firmware: 2.003

Amp Cards used: Minibox Gold, Elfidelity Balanced

Music used:

From Röyksopp to Amber Rubarth, Diana Krall to Apoptygma Berzerk, Tom Jones to Sphongle, Yello to Camouflage, mostly FLACs 24/96 or 16/44.1 – some mp3 320kbps, some AAC 256kbps

Depending on headphone high or low gain – no EQ

Disclaimer: I received the Hifiman HM-901s review unit from www.samma3a.com the local distributor of Hifiman products. I have to return the unit, so there is no financial interest. I am not affiliated with Hifiman or Samma3a.com Though I really highly appreciate what these guys are doing for the audiophiles in the region!! Thank you so much for letting me test and review this player. I had so much fun doing it!!

When I review DAPs I tend to use an input switcher and play the same song on both players, volume matched by ear and switch back and forth. Then I do some extensive listening with the unit and different headphones.

TL;DR

PROS:

Full size SD card slot
Good build quality
Flexibility with amp cards
Easy to use UI
Hard to beat sound quality
Single ended and balanced output.

CONS:

No direct digital outputs (but with included cable adapter)
No case provided
No internal memory
Bulky
No line out (but with included cable adapter)
Price

The HM-901s is the best DAP I have heard so far. Its sound quality beats everything else. The flexibility of using different amp cards is amazing as well as the overall pleasure of having such an amazing device.

Now, the longer version:

Packaging & Accessories

The HM-901s comes in a nice large case and is protected very well. You will get the device itself a battery, a battery charger, USB connection cable, Line-out and coax out converter cable and external battery charging cradle.

Technical Highlights:

DAC Chip: Dual (2x) Sabre ES9018

Ouput: depends on amp card, OP-amp: 627*2, OPA2107*2

Output impedance: smaller than 0.2 Ohm

Headphone out, Digital out (proprietary for charging, line out and Digital (COAX) out.

Size: H109mm, W63.5mm, D15.3mm (compared to oldX5: H114, W67.6, D15.6)

Weight:

Gain: depends on amp card

THD: <0.008% (1 kHz)

Battery: 2,000 mAh (9 hours)

Formats supported:

DSD: 2.8 MHz/1 bit (dff/dsf)

APE (Fast): 192 kHz/24 bit;

APE (Normal): 96 kHz/24 bit;

APE (High): 96 kHz/24 bit;

AIFF: 192 kHz/24 bit;

FLAC: 192 kHz/24 bit;

WAV: 192 kHz/64 bit;

WMA9.1 Lossless: 96 kHz/24 bit;

Apple Lossless (ALAC): 192 kHz/24 bit;

All MP3, OGG, MP2, AAC (as used on iPads, iPhones, iPods)

Size comparisons & Input switcher

HM-901s and AK100 with Gloveaudio A1 comparison.

User Interface and Build Quality

The build quality is very good, solid, nothing squeaks, it;’s a heavy and solid feeling player. Buttons and ports have no play and feel rock solid. The scroll wheel is much improved over the scroll wheel of the original 901.

The machined aluminum case is a joy to hold and handle and it feels really solid and well made.

The User Interface is already known as the Taichi UI and is very easy to navigate and use. There are not too many buttons on the device and the menu structure is very straight forward.

One extremely cool feature of this player is the “instant on” feature. If you don’t change the battery, the device boots from switch off to on in amazing 3 seconds. For everyday usability this is amazing. Think about Android based players that need a minute or more to boot up. This is so much nicer.

Sound Quality

General

Besides supporting most audiophile formats, the player shines with every high resolution format you can throw at it.

The song is musical, detailed and precise. Hifiman commands a very high price for this DAP, so they have to live up to the hype and from my experience, they do.

I cannot emphasize enough how great it is to be able to change the DAP to your specific taste with the use of Amplifier cards.

But that also means that it’s important when reading a review to know which amp card was used.

When you buy the player you can choose between the standard amp cards.

The amp cards available are:

Minibox

Minibox Gold

Classic 2

Elfidelity Balanced

IEM

Sound Quality observations:

From my various digital audio players the only one coming remotely close to the Hifiman is the CEntrance Gloveaudio A1 that uses an Astell & Kern AK100 as transport. Together these two devices are nearly as expensive as the Hifiman. And as bulky but less flexible (no amp cards).

I was pretty shocked when I connected my HD650 to it. They sounded amazing. Then the HE-400, same, then the LCD2 – sublime, then the HE-560 and even these very hard to drive headphones sounded pretty amazing directly from the 901s – that is crazy. For the Planar Magnetic headphones I used a balanced cable and the Elfidelity balanced amplifier card. The result was an amazing soundstage, lovely punchy and tight bass that extended very very low. and just beautiful mids and treble.

In my office I need to use closed headphones, to not bother my colleagues with my musical taste (sound leakage with open headphones). So I opted for the Oppo PM-3 to pair with the 901s.

And as far as audiophile portable systems go, this is the best you can get for combined below $2,000 – a perfect setup that makes you question why you even would bother with a desktop stop at all. You can happily listen to this one at any time. For the Oppo there is not balanced cable officially available but some aftermarket cable makers can make blanked cables for it that will fit the Hifiman 901s. However, you don’t need to go balanced, that is only if you want to squeeze out the last drop of sound quality. The normal output is more than enough for this headphone and I can assure you, you won’t be disappointed.

For the Oppo the differences between the Blaanced card and the Goldbox mini are minimal. So go for any of these two.

Line Out & Digital Out (COAX)

This is only possible with an adapter cable via the multi connector on the bottom of the device. For me a bit of an oversight, it would be better to have a physical port (maybe combo port) on the device. That way you don’t have to carry the additional cable with you.

Anyhow, the cable works well and the line out sounds ruler flat – exactly what you would want. Same for the COAX digital out. Works as expected.

However, the adapter cable is a bit short, assuming that most of the connections on audio devices are on the back of the device, it’s a bit of an odd choice to make the cable so short.

DAC use on a Computer

To my surprise this is not possible without the docking station. For me in a $1,500 device – it’s a must that I can use it as the DAC/Amp on the PC or Mac. Especially because you really want to enjoy this glorious sound anywhere, on the PC/Mac as well.

Hifiman though will sell you a dock that has some amazing additional features.