Suddenly everybody seems to be very into entry level USB DACs. After Fiio and Ibasso, next comes another USB DAC from yet another Chinese manufacturer: Hifiman. As the Hifiman brand is synonymous with high-end stuff, they released the HM-101 under a Hifiman Express brand name.

We’re talking about really entry level stuff here. $39 price tag, and the HM-101 comes in a really tiny size, smaller than the Ibasso D-Zero and the Fiio E10, two entry level USB DACs that we reviewed recently. Build quality is pretty good, though nothing exotic about it. The features are as basic as it gets: 16/48 maximum resolution over USB, a USB port on one side and two 3.5mm ports on the other side.

USB in on one side, analog out on the other.

I have big doubts about the performance of the PCM2702 chip, which is used not only for the USB receiver function but also for performing the actual D/A conversion on the HM-101. I’ve listened to many many PCM270X based DACs, and with the exception of the Styleaudio UD-1 DAC which comes with big PCBs and audiophile grade components, none of the other PCM270X based DACs really have anything good about their sound. Yes, I’m serious. Texas Instruments really designed this chip for basic audio devices such as USB headphones (more like USB headsets), USB speakers (those tiny PC speakers that run from the USB hub), or LCD monitors that come with a built in USB speakers. On some applications the PCM270X tend to be used mostly for USB receiver functions (though being limited to 16/48 most newer products these days tend to opt for the 24/96 capable Tenor TE7022 chip). So I was like “what is Hifiman doing with a PCM2702 chip?”

Good thing that while looking up the PCM2702 and PCM2704/5/6/7 data sheets, I noticed that the PCM2702 had a slightly better numbers on the Dynamic Range, THD and SNR. The PCM2702 also comes with an 8x oversampling filter and a low-pass analog function, something that the 2704/5/6/7 chips don’t have. But at the end of the day, it’s still a PCM270X chip, far from the much more sophisticated Wolfson WM8740 chip used in the Ibasso D-Zero and the Fiio E10, or even the TDA1543 and PCM1704 chip used in the audiophile-grade Hifiman players.

When I first got it, I noticed how simple the operation is. USB input, headphone output. I plugged it in to my laptop, hooked a Senn HD25-1 on the other side, and play some tunes on iTunes and just left it running for a few hours without even listening to it. Then I came back to it, still playing the same album on a loop, and decided to take a listen through the headphones. “Oh wow, this thing sounds pretty good” I thought. I continued to listen. I noticed how grainy and how high noise levels on the HM-101 was, compared to say the black-background of the Ibasso D-Zero and many other DACs I’ve reviewed. But on the other hand the HM-101 does things that the Ibasso doesn’t. The HM-101 had this superb soundstage depth and ambiance that excels anything I hear from the Ibasso D-Zero or the Fiio E10. It’s a bit narrower than the D-Zero, but depth and ambiance was far more real and three dimensional on the HM-101, which leads to a higher overall score on the soundstage performance.

The sound was remarkably analog, and it reminds me a lot of the sound of the HRT Music Streamer DACs. And due to the analog sound signature, I really don’t mind the high noise and grain levels, as it goes really well in the overall presentation, sort of how grain always romanticize film-based photographs, or how pops and noises are an accepted part of the whole vinyl listening experience. The warm and mid-centric tonality is very likable. Not only because it’s warm and mid-centric, but also because you never get a feeling that things are dark and muffled, thanks to the superb, spacious depth of the soundstage giving a very good image of the venue where the recording was taken.

I have no complain with the treble as it was clear enough and wasn’t wrong or bothersome to my ears. The bass, as always, is a bit loose on budget devices, and I’ve learned to accept that compromise as long as it doesn’t go to the boomy category. However the TDA1308 based headphone amplifier lacks the punch in the bass. I think it has enough body in the bass, but just not enough punch and that’s why I’d rather have the signal passed on to a different amp like the Fiio E6 which I already find to improve the bass punch. But obviously that takes out some of the fidelity and the awesome soundstage that I was raving about earlier, and also the beauty of a simple one-box operation. Hence, I would recommend the HM-101 if you don’t mind a slightly less punchy bass section in return for an super-awesome soundstage for only $39.

The headphone amp and DAC section is amazingly free of artifacts as I didn’t pick up anything even listening to the super resolving HD800 and the Beyerdynamic T1. Once again, if the bass was a tad punchier, the HM-101 would have been the perfect device.

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