HIFIMAN EXPRESS Brand and HM-101 Portable USB DAC
Jan 17, 2012 at 11:57 AM Post #33 of 38


Quote:
Heya,
 
So I received the HM101 and put it through some work.
 
Package:
 

 

 
Small, wow, comes with everything you need. It's so tiny. Key chain tiny. This is good. I like small when it comes to this because it's really portable. It comes with the USB cable and the unit itself. Nothing else needed.
 
Construction Quality:
 
It's inexpensive, so expect it to feel that way. It creaks and feels like it compresses when you press it or handle it. It's not super cheap feeling, but it definitely isn't made to withstand wear and tear. So you should take care of it, or it will be a loose little thing. The connections are all tight, so that's good. But the plastic covers move and make noise if you touch them harder than just a gentle brush. I'd had hoped for something reinforced. It feels like there's nothing sturdy behind the black plastic covers, you could push through. The unit is very light weight, it feels like you could blow it out of your palm with an exhale. It's not a very dense object.
 

 

 

 
Style:
 
It's external, so style matters. I think it's a gorgeous little unit. I like the classy look of most of Hifiman's stuff. It has a retro font with a classy overall modern appearance. The blue LED is nice, and not overbearing. Looks good. Style points.
 
Connectivity:
 
I plugged her in and she was detected immediately. Showed up as "Burr-Brown Japan PCM2702" speakers. I simply set as default (or selected in Foobar2000 as my output device) and was playing music. Very easy to use, fast response, works without any trouble. This was tested on Win 7 x64. It has a phone jack that is amplified. It also has a line out, so you can use it to output to another more powerful amp or to a set of powered speakers. I tried it out with my M-Audio AV40's and it worked great (powered monitors) for a compact external system that can plug into any laptop/netbook. I also used it to output to my other amps and that worked fine too. Ideally though, if you're just looking for a DAC/AMP this is all you need, but if you're using it to simply output to another amplifier, I would look at a better more discreet DAC option with a different connection type (like optical/SPDIFF, I would probably get the Fiio D3 instead if simply outputting to another amp).
 

 

 

 
Sound Quality:
 
The sound is warmer than I expected, it really was a musical sound, less of an analytical sound. However, the noise floor was really high I found. Also, your USB port has to be very sturdy or you'll hear it. I tested it on several different computers and several different USB ports. I found that if the USB connection wasn't really, really tight, it would add sound as it moved, so I found that to be an issue on older machines or heavily used USB ports that are not very tight after a few years of use. In a really tight USB port, I had zero issue though. The noise floor is high as I mentioned, it's the first thing I noticed. Compared to some of my other DACs which are dead silent when I have something plugged in or playing quietly. I can hear a lot of hiss and noise floor from the HM101 regardless of what headphone I plug in. It's not super loud, but it's definitely noticeable when you come from a good DAC that is silent. I imagine this might have something to do with gain and you cannot change any settings on the HM101, so that's just how it is. I plugged in some SRH940's to reveal any detail the HM101 would give off that isn't in the recording, and boy it did, there was that noise floor. The noise/hiss was less noticeable in other headphones I used that were more forgiving of source. If you have analytical/detailed headphones for primary listening, I wouldn't use this DAC/AMP. It's just too noisy for me in combination with a headphone like that. If you have some more musical/warm headphones that are a lot better with noisy sources or simply forgiving of source, you will have a better listening experience with the HM101. Granted, this is still better quality reproduction than typical onboard sound for a lot of laptops/netbooks. But, I'm not so impressed with it compared to discreet soundcards. I have a Xonar DG and Auzentech Forte and didn't find it to compete at all with either of them. So someone with a full size machine would benefit from a different device unless they strictly wanted a mobile tiny device like the HM101. On a laptop/netbook where upgrading onboard is not an option, this HM101 makes good sense. It gets you off the noisy onboard. However, again, you still have to deal with USB noise and potential added noise if the USB port is not very tight or connective.
 
Sound itself was good. Detail came across well, I had good crisp highs, good mids, clarity, and the overall signature was warmer than some other sources I've compared to. I wouldn't call it special compared to things that cost equivalent or higher than it though. It's not better than a typical sound card. But it is better than a bad quality onboard sound option. Note, some onboard options are actually really good and superior to this unit. I think the highs are a little bright, I noticed some of my headphones gained some edge to them that was not previously there.
 
The amp side can push headphones quite nicely. It won't take care of maximum impedance inefficient insensitive headphones. But it will power most headphones without much effort. It even can power an ortho. I plugged my HE-500 directly into it with an 1/4" to 1/8" adapter and it actually played music just fine. It was a little bright sounding compared to normal, and I didn't get any clipping. I did notice I lost a lot of volume in the low end, but I was still able to get low tones without clipping. So it can drive even the HE-500 if you wanted to go portable with some high end orthos. Kinda cool. It won't be driving them to their full potential. But it's definitely capable.
 
I had to turn down the volume on my SRH940's to about 25% on FooBar2000's volume slider. At 100% it's way too loud. So this little guy has a lot of room to output volume.
 
I plugged a pair of Sennheiser HD650's to test higher impedance headphones and of course, see if it could power the sleeping giant. It powered them. I had to put the volume slider to 100% to have just a hair over my listening volume, so it was just adequate. I definitely noticed it was brighter on these headphones compared to a better balanced DAC. I mean, bright HD650's? I was getting fatigue from some dubtrack from some high pitch tones and synths. So that definitely gives me the impression that the HM101 adds significant brightness to the highs of headphones (which explains why the SRH940 was so harsh to listen to on this HM101 since it starts out so forward as it is). The bass was definitely not coming to town. It was muddy, clipping a little, and not controlled. So the HM101 cannot power mid-impedance or high-impedance headphones with authority. I'm getting bass, mind you, it's playing the tones, but the control is clearly not there when I compare it to a sufficient amp. I wouldn't put some 250 / 300 / 600 ohm headphones on the HM101. Basically anything under 250 ohms would be ok likely. This is right in line with most base sound cards so that makes sense.
 
I felt like it's ability to drop power on a low end tone wasn't sufficient. I noticed a lot better impact in low tones (using dubstep tracks) from other devices. I was able to get the low tone played, without clipping from the HM101. But, it definitely lost impact and had less presence that various headphones on more capable amps had. This is not a con really, since this is an inexpensive portable combo unit. It's actually impressive that it's able to do this much with most of my headphones to begin with. But don't expect it to drive most headphones to their full potential. It will get them nearly there, but not all the way. Some headphones really are sleepy after 98~99% of their potential until you give them ridiculous amounts of power.
 

 

 
Conclusion & Thoughts:
 
For the money? Sure, I'd recommend this. It's a good little DAC/AMP for someone that wants something simple, small, and portable. I would not recommend it for someone with a headphone that has significant power requirements. If you have a pair of low impedance and sensitive headphones, this will work great. I think it pairs poorly with detailed or analytical oriented headphones. That is, unless you want to hear a lot of stuff that is not very pleasant, but if you're critically listening for artifact and issues with a recording, it will definitely reveal them to you. That's good or bad depending how you look at it. Based on how it sounds, I would not put it with things like the SRH940 or the KN6400. I would also not put it with a Grado of any sort. It will just hurt. I would however pair it with already relatively dark or warm headphones. It adds brightness and warmth as it is, so they won't be as bad when paired up. The warmth is in the mid/upper bass, not the lower bass, it's power is insufficient to enhance (color) the sub bass, but that's ok, it's not a powerful amplifier, so it's not expected. If you're using a computer and you want a good DAC/AMP and you can install a sound card, I'd suggest you get a Xonar DG instead. It's better control, has dolby headphone, etc. Simply a better investment for that situation and covers more headphones. If you want a portable DAC/AMP for low impedance headphones that will work from your laptop/netbook or on someone else's computer when you move around or to take to class, school, work, then this thing will definitely fit the bill.
 
If I had to scale it, I'd say it's about a 6 out of 10 overall. So, better than average, but not something I'd call exquisite.
 
Very best,




Great review and I would have to agree with most of your points. I recently bought this for my brother as a gift but decided I wanted to test it first. I used some HD 600's and Shure SE535's and found that the hissing and noise floor to be extremely annoying, especially when I'm listening to a live concert where there are fade in/outs when transitioning from song to song. Noise was more noticeable at a lower volume than at higher volume. I'm using one right now for my work computer and speakers as I can't upgrade the computer. Didn't want to put any money into this set up either since I do most of my listening using a docked iPod to a Cambridge Audio Sonata AR 30 hooked up to some speakers and sub. Yes, I have a 12' sub in my office at work. My boss and neighbors aren't very thrilled about it......
 
As previously stated, you get what you pay for. Would I recommend this unit? Yes. Just depends on what you're plugging into it. You could tow a smal boat with a geo tracker and get the job done, but you're not going to get the performance you'd like and there are going to be flaws.
 
Overall-  5 out of 10
 
Feb 4, 2014 at 4:04 PM Post #36 of 38
I just got this -- astoundingly good sound for very cheap. Some comments about the noise floor: the line output is MUCH cleaner in terms of noise than the headphone output. It is quite possible to listen to this using the line output. But much of this is due to the isolation or lack thereof of the power coming from the laptop itself. My Macbook Pro has pretty clean power so there isn't nearly as much noise as I suspect some of you are hearing.
 
Secondly it matters where you place this, and what is close to the wires. If your phone gets too close, etc., you will hear more noise. I suspect a higher quality USB cable could make a difference. Also --- a high quality powered USB hub does seem to reduce noise (I used a Belkin).
 
With my Macbook Pro I find the noise floor acceptable even though the headphone out, and I prefer the sound of the headphone out so I'm using it. But I have driven my car stereo with the line out and it is a spectacular improvement over the head unit's DAC or a raw iPhone.
 
One tip when using this with the Lightning to USB Camera cable from Apple and an iPhone --- if you are using a powered hub (as I am --- it's kind of a hokey setup, I put my Radio Shack AC inverter into the AC adapter for a Belkin powered hub, so the Hifiman is powered by the hub instead of the iPhone --- it is important to connect the cable to the iPhone AFTER the powered hub is powered up, otherwise power drains on the iPhone despite the powered hub. My guess is the iPhone senses whether or not it needs to provide power to the device when you plug it in, and if the powered hub isn't active yet, it will try to provide power that isn't needed. I found when I turned the ignition on I had to unplug the cable from the iPhone and plug it back in to get the power drain to go to reasonable levels.
 
So, this device isn't really good for portable use with an iPhone --- battery drains too fast. I can't tell exactly but it might be only an hour or so, maybe a little more. I think an iPad has enough battery it could be usable for a while. With a powered hub, however, it is usable with an iPhone, but again the iPhone can't be charged in this configuration.
 
Mar 21, 2014 at 8:12 AM Post #37 of 38
Hi all, I'm planning to use this with my Shure SE 215's , sources will be Sony Xperis Z-1 and Apple Ipad. Would it make a big difference? (Sound wise) Thanks for replies.
 
Dec 9, 2014 at 1:59 PM Post #38 of 38
Hey guys, I just saw this little dac/amp and i think i want to buy it :p
My samsung S3 jack is a bit broken and i lose audio then i move, so want to connect the phone with the dac via USB (obviously)
Should i stick with that plan or should i buy a DAP?   (i don't want to change my phone)
 

Users who are viewing this thread

Back
Top