HiFiMAN HE400
 
 

 
 
By now I think most of us are familiar with the history behind the HiFiMAN HE-series headphones. What started with a single model has grown into a full lineup, with prices ranging from $1299 for the flagship HE-6 to just $249 for the entry-level HE-300. Worth noting is that the HE-300 stands apart from the rest by using a “traditional” dynamic driver. Every other model in the HE-series is based on planar magnetic driver technology.
 
The entry level position among the planar models is held by the HE-400. It is the most recent HiFiMAN headphone released and sells for $399, putting it in competition with some more established designs such as the Sennheiser HD600/650, AKG K701, and Denon D2000. As the only planar model available in this price range, I was curious how the HE-400 would measure up.
 
Those who follow my ramblings here know that I have a newborn baby in the house. Accompanying the birth of that little guy was a major purge of my open headphones; the logic being that I wouldn’t be getting much use out of them. So I sold my Sennheiser HD600, HD650, and HD800, my Grado PS1000 and RS1, and my Beyer DT880 and DT990. I also passed on buying the Audeze LCD-2 and HiFiMAN HE-500, which I have borrowed from friends multiple times and really wanted to own. Yet here I am with a new open headphone – why? The answer is simple: it’s one thing to have a $900 or $1,000 headphone sitting around getting little use. It’s quite another matter with a $399 model. I figured I would start small in the HiFiMAN lineup and make my way up the ladder when the time is right. Since then, the HE-500 has dropped to $699, but the point remains the same.
 

 
 
DESIGN
One would think that HiFiMAN must have cut some major corners with the HE-400 to allow pricing it at nearly half what the HE-500 sells for. But one would be wrong in that assumption. HiFiMAN claims the key to the low price is the use of automated manufacturing techniques. Apparently their planar magnetic designs are mature enough by this point to allow some level of hands-off construction. If anyone has ever seen the episode of “How It’s Made” showing the AKG factory building K702 headphones, you’ll note how automation makes the process many times faster and more efficient than it otherwise would be. There is still an element of human involvement but it is reduced in many key areas.
 
Think of a handmade… well, anything really. Whatever it is you picture, it’s going to be labor intensive to build. It’s also going to be expensive compared to an assembly line type operation. And it’s going to be more prone to have variability and likely a higher rate of flaws. Until now, it seems that all HE-series headphones were hand crafted. That sounds impressive but in reality there have always been issues with the method – think Audeze LCD-2 and LCD-3 sounding different from one example to the next. Think the initial run of the Grado PS1000 and the often disappointing silver finish. With the HE-400, HiFiMAN has automated the process of producing the driver, and I suspect at some point soon they will have more of the process automated, similar to AKG. The bottom line here is that the HE-400 may have otherwise been slapped with a $500 or $600 price tag if this new development process had not been achieved. So don’t think of it merely as a “budget” headphone with all the negative connotations that go along with that thought. Rather, think of it as an “optimized” design which allows the price to stay relatively modest.
 
In terms of appearance the HE-400 is very similar to its HE-siblings. The key difference is the blue paintjob, which I actually find more attractive than the usual dark color of the other models. Other than that we get the same leather headband, the same frame assembly, the same detachable cabling system, and the same earpads. But there are a few significant differences worth noting.
 
First, and probably most important, are the drivers themselves. They have smaller magnets and appear less complicated compared to the older models. While the HE-500 driver assembly looks like a fancy cheese grater, the HE-400 uses less complex perforations and a good amount of plastic. There’s also the earpad attachment system which is far better than the older “tab” system. It still isn’t perfect but I was able to swap pads several times without wanting to throw the headphones out the window in frustration. I consider that improvement. I believe all of the HE-series models are now using this new system. Then there’s the packaging and cable differences which I’ll discuss a bit later.
 
Here are the pertinent specs for the HE-400:
[size=12.0pt]·       [/size][size=12.0pt]Efficiency: 92.5 dB/mW[/size]
[size=12.0pt]·       [/size][size=12.0pt]Impedance: 38 Ohm[/size]
[size=12.0pt]·       [/size][size=12.0pt]Planar Magnetic driver (orthodynamic)[/size]
[size=12.0pt]·       [/size][size=12.0pt]Frequency response: 20 Hz to 35 kHz[/size]
·        [size=12.0pt]Weight: 440 g[/size]
In comparison, the HE-500 is 89dB and 502g. That means the HE-400 is lighter and easier to drive. Supposedly one could even run the HE-400 straight from an iPod, though I can’t imagine a scenario where I would actually want to do that. This is certainly not a portable headphone. Still, the prior HE-series models were known to bring many headphone amps to their knees, so the improved efficiency is very welcome, as is the reduced weight.
 

 
 
BUILD QUALITY
Like the prior models, the HE-400 is nice but not perfect. It doesn’t have the same level of sophistication and “tightness” that something like a Sennheiser or Audio Technica would have. But overall it is acceptable for the price. The blue finish is attractive, and there is a good mix of leather, metal, and plastic. The new pleather earpads feel decent as far as pleather goes. I’m not usually much of a fan and I would have preferred the velours instead, but I’ve seen far worse. The new pad attachment system does allow the pads to “spin” more freely than I’d like. It’s the only area that feels to me like it isn’t of very high quality. Yet the pads never fall off and are fairly easy to swap, so maybe I shouldn’t complain. 
 
PACKAGE
Prior HE models came in a nice looking storage case. In contrast, the HE-400 ships in a fairly basic plastic package as if it was a $50 headphone. As much as I miss the “wow factor” of the fancy box, I’m actually glad it was omitted here - unnecessary extras are just what you don’t need when trying to keep prices low. HiFiMAN does throw in a storage pouch which I’ve never once used; I guess it’s better than nothing and some people might have use for it. HiFiMAN sells a nice travel case for $29 if anyone desired such a thing. My HE-400 lives on a headphone stand so I’m pleased that I wasn’t forced to pay for a storage case that I’ll never use.
 
Prior models included a single spare earpad. I always thought that was strange – why not a pair? The HE-400 solves that strangeness by no longer including anything. And that’s fine by me. Additional sets in velour can be had for just $10 a pair.
 
The included cable is 10 feet long, terminates in a 1/8” plug, and is fairly thick and unwieldy. For me, this was the biggest letdown of the whole experience. I recall not being a big fan of the HE-500 cable, so I knew this one would probably be bad, but over time I came to really dislike it. It was an easy fix due to the plethora of aftermarket cable options on the market. Some people may not be as easily annoyed as I am, and may find the stock cable totally acceptable.
 
EQUIPMENT
This is the equipment I used for my evaluation of the HE-400:
 
Source: JF Digital HDM-03S music server, Squeezebox Touch, Marantz SA-1
 
DAC: Violectric V800, Anedio D2, Yulong Sabre D18, Matrix Quattro DAC, Kao Audio UD2C-HP, Grant Fidelity TubeDAC-11
 
AMP: Analog Design Labs Svetlana 2, Violectric V200, Yulong Sabre A18, Matrix Quattro Amp, Lake People G109P, Apex Butte, Audinst AMP-HP
 
Cables: As I’ll discuss later, I didn’t care for the stock HE-400 cable. So I replaced it with a CablePro Earcandy for single ended use and a Toxic Cables Hybrid for balanced operation.
Earpads: I swapped out the stock pads for a set of Lawton modified Denon D7000 pads. I’ll explain later.
Power was handled by a CablePro Revelation conditioner and CablePro Reverie AC cables. Interconnects were Signal Cable Analog Two for RCA and Paillics Silver Net for XLR. The HE-400 was burned in for well over 100 hours prior to doing any critical listening.
 

 

 

 

 
 
LISTENING
I have to preface this by telling my story about the pads. The stock pads are actually pretty nice - I was worried that I would have major isses with overheating, but that ended up not being the case. No, my issue was on the left side of my head apparently being a little lumpy. Behind my left ear, the stock pad would leave a tiny gap smaller than my pinkie finger. No amount of fiddling with the headband or cup angle seemed to remedy this. I've never had this issue with any of the dozens of headphones I've used, including the HE-500 with velour pads. I can’t fault the HE-400 but rather my own uneven skull. In any case, the gap caused a small but audible difference in sound from left side to right.
 
Obviously I couldn't eveluate the HE-400 without a proper seal. I borrowed an HE-500 from a friend but it used the older mounting system, so the velour pads were of no use. I was considering ordering a set (they are very reasonably priced) when I had an idea - why not try a few other pads that I have around the house? The very first set I found when I went digging in the drawer was from a Denon D7000. It had been modified by Lawton Audio when I sent my D7000 in for upgrades. When Lawton returned my Denons in LA7000 form, I never actually used the pads, opting instead for the J-Money V3 pads. So these Lawton pads were just waiting for a new home. For those unfamiliar, Lawton stuffs the pads with extra Poly Fil type material, especially to the rear area, which makes them look somewhat like an Audeze LCD-2 pad. It makes a great seal with my (apparently oddly shaped) head, and helps position the drivers at an angle to theoretically give a more speaker-like presentation. All of the impressions that follow were obtained with the Lawton pads in place. Since I couldn't get a good seal with the stock pads, no comparisons are possible. That might invalidate some of my impressions but there’s nothing I can do about it.
 
The sound from the HE-400 was immediately appealing to me. I heard the typical "planar" presentation which I categorize as having a sort of effortless sound to it, with excellent deep bass extension. I don't know how better to describe it, but it’s something that the LCD-2, Thunderpants, and HiFiMAN models all have in common, despite all sounding very different from one another. There's just an ease to the presentation that dynamic headphones can't quite match. I'm not saying planars are always superior, but this is one of their strengths.
 
Bass on the HE-400 is very nicely done. It isn't huge, but has enough of a solid impact and presence to be satisfying for all but the most extreme basshead listeners. Where similarly priced dynamic headphones from Sennheiser, AKG, and Beyerdynamic all have rolled off frequency response in the sub-40Hz range, the HE-400 (like most planar models) stays almost completely linear down to 25Hz or so, with a very mild drop below that. To my ears this ends up sounding more convincing; as if more air is being displaced. And maybe it actually is. The bass presentation is very close to that of the HE-500, lacking only a small amount of texture and refinement in direct comparison. On its own though it is some of the best low frequency reproduction I’ve heard from a non-flagship headphone.
 
Mids on the HE-400 are somewhat forward. This gives it a more exciting sound than the more neutral HE-500. There's an added "bite" to things like trumpets and violins, making for a very engaging listen. The mids have a nice smoothness to them though, meaning they aren't just run of mill, average quality stuff being boosted to sound more exciting. They really do have enough clarity and focus to pull off this little trick. Upper mids are somewhat subdued, which generally makes for a smooth presentation though it can occasionally take away some realism in the form of a lack of airiness or trailing edge. This was mostly noticeable with really well recorded tracks – on lesser material it could actually help hide some of the harshness from poor mastering. So it ends up being a give and take.
 
As with many headphones, the highs of the HE-400 are the one area where it isn't perfect. It isn't terrible either, but this is where I heard the biggest divide between the HE-400 and HE-500. The 400 has a bit of darkness to it but also has some brightness. "Dark and bright at the same time? How can that be?" Take a look at the Frequency Response chart as measured by Tyll at InnerFidelity. Notice the “droop” starting at roughly 1.5kHz which doesn't pick up until around 7kHz. From there it actually gets somewhat bright, and that's exactly how I hear it. Brass and woodwinds, while seeming fairly cool and dark overall, also have some "zing" up top peaking at 9kHz or so. This can sometimes come across as a bit brittle or harsh. Other times it is inoffensive and actually brings out some extra perceived detail. It works more often than not, but it must be mentioned because certain people are more sensitive to these types of peaks. I also need to point out how hard it was for me to wrap my brain around this presentation. With female vocals for example, you hear something of a darker presentation with less air or breathiness, which would normally be smooth all the way around. But then you get this peak which tends to accent certain consonant sounds, not quite sibilant but borderline.
Once Tyll got his measurements posted it started making more sense, though I do think my pad swap has helped the problem somewhat. I know people who use the velour pads and they report a subjective improvement as well, so that's something I definitely think is worth exploring since it costs so little.
 
I was surprised that the HE-400 was able to pull off a reasonably large and very well defined soundstage despite being on the darker side. Planar models tend to not have the most spacious presentation anyway, and the same goes for darker headphones in general. So I figured the HE-400 wouldn't have much going on to brag about in this area. Perhaps my angled pads are doing a lot to help, but I really do find these to be nice and open sounding, with good definition of the musical space. Imaging is accurate and there is some really nice layering going on. It might not be up to par with the HE-6 or HE-500, but it is definitely near the top of the pack in the "mid-fi" range where HiFiMAN has positioned this model. The K701 and variants might be more spacious but it comes at the cost of being somwhat artifical.
 
 
AMPING
The HE-400 is supposedly the planar for the common man. It doesn't require heavy amplification, so one could reasonably use it from a fairly low powered amp, or even straight from a DAP. That's the theory anyway. In practice I found that to be only partially true.
 
Yes, my iPad and Sansa Clip can drive the HE400 to reasonably loud levels, and the resulting sound is certainly listenable. But I don't enjoy it nearly as much as I do when adding even a basic amp like my portable Audinst AMP-HP. Specifically, the bass presentation is nowhere near as satisfying until a separate amp is involved. And the highs are much more prone to offend with that “edginess” I mentioned. The only exception to this amp required rule might be some of the "premium" portable units such as the iBasso DX100 or HiFiMAN's own HM series. I did try my RoCoo D Power Edition and the result was reasonably good – better than my iPad, but still not great. Ultimately I would never use this as a portable headphone anyway so I don't mind the amp requirement.
 
As far as which amps work best, it becomes a question of sound signature preferences. All amps have their own unique presentation, and while the differences are not always huge, you want to pick one that best fits your predilection. I found that I enjoyed the HE-400 with all of my desktop amps, but some were better than others. I don't care how sensitive they are, planar headphones seem to always respond to power. For that reason the powerful Violectric V200 and its cousin the Lake People G109P did a fantastic job. The V200 had a little more clarity on the top end but for the most part the cheaper G109P was able to keep up.  I also liked the Apex Butte and the Analog Design Labs Svetlana 2 for their exceptional midrange presentation. The Matrix Quattro amp in balanced mode offered an enjoyably smooth, refined presentation for a low price. But I think my favorite pairing is with the new Yulong Sabre A18 amp in balanced mode. This is a Class A, fully discrete, differential design that just mates perfectly with the HE-400. It delivers just under 2 full watts per channel to this particular headphone, bringing it close to the V200 in terms of current delivery. But it has an exceptionally expansive soundstage that sets it apart from the Violectric model. It isn't always better with every headphone, but the HE-400 seems to be a perfect match. Single ended mode was good too, but not quite up to the same level, and in that situation the V200 regained the lead. For anyone interested in balanced operation, I highly recommend the A18/HE-400 pairing.
 
With a seemingly dark headphone like this you don't want to obfuscate any of the top end presentation by using a darker amp. Yet the sometimes peaky highs also don't need any extra attention either. So keep in mind when planning an HE-400 based system: a generally neutral amp is desirable over one with a strong coloration of any type.
 
COMPARISONS
I have owned most of the similarly priced headphones that would be considered competition to the HE-400. Unfortunately I no longer have any of them on hand for direct comparison. But I'm familiar enough with them to make some generalizations.
 
The AKG K701, and its brethren in various colors, are very different from the HE-400. Almost complete opposites - they have significantly less low frequency resolution, and as a result give the impression of significantly more energy in the upper mids. Personally I would choose the HE-400 every time, except perhaps in the categories of comfort and soundstage size.
 
The Sennheiser HD650 is still a killer headphone in my opinion. I think it offers a more even, linear presentation from top to bottom, while the HE-400 is far more exciting and dynamic. These two would actually complement each other quite nicely if a person wanted to own two headphone for two different takes on their music.
 
The Beyerdynamic line of DT770/880/990 is in process of being replaced by the new T70/80/90 models. But not all of those are released yet, and way more people have experience with the DT series. So this is still a fair comparison. The HE-400 strikes me as being somewhere in between the 880 and 990, but superior to either. It has less bass quantity than the 990, but to my ears it does lows in a much more convincing manner. Sub-bass extension is superior to the point where it just makes the 990 sound bad in comparison... and keep in mind that I actually do like the 990. Mids are more forward than either Beyer model, which is a welcome improvement in my opinion. Highs reminds me more of the 990 but are not an exact match - I hear the HE-400 as being less grainy and having a more natural flow; even though they do both get harsh on some tracks, the 990 is clearly the bigger offender.
 
CABLES
I mentioned prior that I disliked the length and thickness of the stock cable. So I picked up two different aftermarket cables to try out. Both of them are miles ahead of the stock cable ergonomically, and both happen to look much better as well.
 
The first is the CablePro Earcandy which is currently on sale for $109 (regularly $129) for a 10 foot length. Construction is described as finely stranded 22 gauge OFC conductors, with a low-loss polyethylene dielectric and an OFC braided shield to block noise. Mine has a 1/4" Neutrik plug for single ended operation though other options do exist.  This is a very flexible cable with a low key, classy look to it that exudes quality while still remaining understated. It reminds me of the Cardas Sennheiser upgrade cables, but obviously priced way lower. I have to say I’m exceedingly pleased with the service I received from the company - CablePro sells all kinds of products (several of which I own) and they are extremely pleasant and helpful.
 

 

 

 

 
The other cable I got is from Toxic Cables. Based in the UK, their Hybrid cable uses a combination of cryo treated OCC copper and cryo treated OCC silver plated copper. I got mine with balanced termination though again, other choices exist. As of today's exchange rate the price translates to $134 for a 6 footlength. This cable looks like it should cost significantly more than it does – if the color was different it would looks a lot like the older (and rather expensive) Lawton Audio Jena Labs recable jobs. The best part is that it’s surprisingly flexible and easy to manage. I refuse to deal with an unwieldy cable no matter how nice it might look, so this aspect is critical for me. Toxic Cables is also a great company to deal with, and is actually an authorized HiFiMAN distributor as well - so headphone and cables could all be ordered together if one was interested. 
 

 

 

 

 
 
With a new headphone to figure out, a newborn baby in the house, and plenty of other reviews on deck, I don't have time to get into a cable debate here. I did let a friend who is a certified cable nut (and has way more free time than I do) borrow both cables, and he loved them. He normally uses Moon Audio Silver Dragon V3 cables for his HE-500 as well as his original HE-5. In his opinion, both the CablePro and Toxic Cables products were just as good as the more expensive Moon option, and possibly better. He said he liked the Earcandy more with his Cary Xciter amp driving the HE-5, and the Hybrid more with his HE-500 powered by the Red Wine Audio Audeze Edition balanced amp/DAC unit. Something about "synergy". Neither of those amps are high up on my list of favorites, so obviously he and I have different tastes. Yet we both enjoy these cables. I intend to keep them both - one will stay with the HE-400 and the other will pair with some future flagship HiFiMAN model that I'll eventually pick up.
 
CONCLUSION
HiFiMAN has done an excellent job of tuning the HE-400 to have big, bold sonics with any type of music you throw at them. The low frequency capabilites are very impressive, sounding very close to the much more expensive HiFiMAN models. And the mids are wonderfully engaging - nobody would ever call this a boring sound signature. The only area of concern is the highs; most of the time it is smooth, slightly dark, and generally inoffensive. Every once in a while it becomes just grating enough to remind the listener that this is in fact still a "budget" model. 
 
It sounds like I'm being hard on the HE-400 with my description of the highs. I don't mean to be picky and I don't want to overstate the problem. These really are excellent sounding headphones in the sub-$500 price bracket - a bracket where all entries will be flawed in one way or another. To some extent you have to pick the flaw which you find least offensive and go with that one.
 
I will say that these are my current favorites in the sub-$500 range. The HD650 is still an excellent all purpose model that could be a suitable counterpart for the HE-400, but if I had to choose just one I'd go with the HE-400 first. The Grado RS-2 might be more exciting for a very limited selection of music, but with everything else the HE-400 leaves it in the dust. Believe it or not, I could totally see the HE-400 being preferred over the HE-500 for some listeners. I think HiFiMAN has done a great job with this release and I can easily recommend them to anyone looking to purchase a good sounding headphone that isn't astronomically priced.
 
 

 

 

 
 

 
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Disclaimer: A big thank you to Electromod for loaning me the HE-400.
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For those of you who don't already know - Hifiman are a Chinese company, although technically founded in New York (2006), their R&D department is in China. In just a few years they've made quite a name for themselves making high end portable audio players, amplifiers and headphones. For the latter their focus has been with 'planar magnetic' (commonly and less correctly referred to as orthodynamic, or 'ortho'), apart from their entry level model, which costs £300. The ortho's range in price from £400 to £1000, but share a very similar design - essentially only the colour changes. Their model numbers can be a little confusing too, so let me try to get my head around this hierarchy:[/size]
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Their current flagship model is the HE-6. This now has a baby brother with the HE-4, but originally the next model down was the HE-5 and that was replaced by the HE-5LE. Both of the HE-5 models have now been phased out and replaced by the HE-500. Finally there's the focus for this review - the HE-400, which is the company's cheapest and most successful selling ortho to date. [/size]
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Hifiman have made a couple of other interesting products recently too. Like the EF-6, a high-end headphone amplifier that partners with the power hungry HE-6 headphone. Then there's the EF-2a, an affordable ($169 US) USB DAC and tube amplifier. More recently Hifiman have been branching out into in-ear monitors, with the RE-400. Let's not forget about their portable audio players too. Models like the HM-801 and the more reasonably priced HM-602, I've always been interested by these, but unfortunately never got the chance to try them. So they clearly have the audio pedigree, albeit a pretty short one. [/size]
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I've tested a lot of open back headphones lately, with the DT880, HP200, GMP400. Plus although I haven't reviewed them, I've spent quite a bit of time with the Sennheiser HD600 & HD650 too, so let's see what I think of this more expensive newcomer.[/size]
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     SOUND[/size]
[size=medium] The HE-400's sound is well balanced, but it's also very impressive and exciting. The real icing on the cake for me is their versatility with various genres. It's an airy and clear sound with slightly warm leanings. There's lots of presence and body here, but with very little colouration or fatigue. Bass almost verges on the epic considering it's control. Mid-range is clear and detailed, while the upper ranges sparkle without being harsh. The soundstage is wonderfully spacious and three dimensional, as is instrument separation. [/size]
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That pretty much sums up the HE-400 for me, it's a stunningly likable headphone. There really isn't much to complain about in the sound department, even at this price. If the Sennheiser HD600 was a little cheaper I would say they are equally matched for value, but this is purely based on sound. I have a couple of reservations about the HE-400's comfort, but also at the HD600's price point I would still give the overall crown to the Hifiman. Damn it! Now I'm getting into comparisons, OK I'm struggling to say more here so I will move on and go into more detail later on...[/size]
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     AMPLIFICATION[/size]
[size=medium] Running the HE400 from my phone (Galaxy Note 2) and trying to get the sound loud proved a bit of an issue. At maximum setting it was about 90% of the volume I wanted for Electronic music, which means it would be about 70% for most classical music. That's unfortunate because the sound quality wasn't too bad, but let's face it, if you're looking at these headphones you will most likely already have some decent amplification for them. [/size]
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Proper amplification wise I started with the Schiit Modi and Magni, which have a tremendously compelling performance that combines very well with the HE-400. I can see why Electromod concentrate on these two brands almost exclusively, you can't go too far wrong with them. The only down side is that the three entry level models will set you back around £600, which is a lot to swallow in a single purchase for many people. Perhaps it's slightly over the sweet spot of diminishing returns too, but wow does it attain a seriously compelling sound![/size]
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Next up I partnered the HE400s with a nice portable solution for laptop use with the Ifi iDAC (combined DAC/amp that I will be reviewing soon), which is rather unusually is capable of 24bit 192khz through USB and is purely powered by the USB bus. The only other unit I had like this was the iBasso D7, which I also tried with the HE-400. The D7 Sidewinder was actually a lot better than I remember, possibly because it's better suited to more demanding headphones like this. Anyway, it still exhibited it's typical power issues when plugged into the non-powered USB ports of my laptop *sigh*. The Ifi iCAN showed no such power issues and drove the HE-400s loud and well, no matter what ports I connected it to. This was not as a compelling sound as the Schiit combo, but don't forget this is a lot more convenient if you're away with a laptop, or perhaps a Windows surface?[/size]
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I also plugged the HE-400s into the Benchmark DAC2 HGC. This combined DAC/amp might be ridiculously more expensive than the HE-400, which are not cheap already, but it was understandably entertaining. On the Fostex TH600 (also being reviewed soon), the DAC2 was almost surreal in it's separation, but the HE-400s soundstage stayed a little more reasonably great and retained a level of coherent realism as well. The imaging was still given a wide push compared to anything else I tested it with and it is lot of fun. I'm left feeling that you can safely spend considerably more on amplification with the HE-400s and keep getting tangible improvements, where that same investment could be a waste with other headphones.[/size]
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[size=medium]     MUSIC[/size]
[size=medium] Here are some individual music tracks and how I felt the HE-400s coped with them. Most tracks were listened to in CD format with lossless compression. All tracks are also available on Spotify, which on the 'premium' service are maximum quality MP3s and I find these highly acceptable.[/size]
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1. Jesper Kyd: "State Of Decay Main Theme" - I actually don't know what this is a score for, I just follow the Danish composer because I love some of his other game soundtracks.   One of reasons the HE-400 is so good with Classical and soundtracks is it's nicely flat response, although flat can sometimes mean a bit boring, it certainly doesn't here. There is a quality and emphasis to the bass and treble, while not being offensive and that really makes these headphones special!
2. Excision: "Deviance - Original Mix" - With the HE-400s superb upper bass body I had to try some nicely powerful Electronic / Dubstep type tracks. This one has some great & dynamic bass! The HE400s do a stunning job of rendering it without any mid-range contamination. This is one of those headphones that can be addictive for bass as well as agile and powerful, yet delicate for something like classical.
3. Jason Mraz: "I'm yours" - The bright and crisp vocals are beautifully presented, produce zero harshness and have a great sense of air. I want to say that these headphones make a compelling argument for vocals, but again it's their versatility that seems to really stand out.
4. Fear Factory: "Replica" - The HE400s transition from delicate vocals into aggressive death metal with ease. There's great attack and speed from the guitars, while aggressive vocals are clear and nicely separated as possible. This is as good as I've heard this music. 
5. Amy Winehouse: "Back To Black" - This track has nice sense of smoothness and good emphasis on vocal clarity. It's as entertaining with slow or simple music as it is with fast, densely packed instruments fighting for attention. 
6. Orishas: "A Lo Cubano" - This latin pop is extremely enjoyable through the HE400s. It's a nicely mixed, dynamic sound that will have you foot tapping at the very least and these headphones bring out the full soul of the music. 

[/size] [size=medium]      COMPETITION[/size]
[size=medium] Comparing these headphones to others can be rather difficult. There are clear differences and advantages to orthodynamic drivers and the problem with comparing the HE-400s to other orthos is that there's nothing else in quite the same price bracket. On the low end there's Fostex's most expensive orthodynamic headphone - the T50rp (£100). The best option here is to compare the HE-400s to a modified T50rp, like the Mr. Speakers 'Mad Dog', there are several others, but this is one that I've reviewed. At around £300 this is a much closer price to the HE-400 and luckily I still have them here to compare. The only other orthodynamic manufacturer around is Audeze, but their cheapest model is twice the price of the HE-400 and is a lot harder to find. This means that the next most expensive ortho after the HE-400 is HIfiman's own HE-500 (priced at £700), so you can see the problem. So for this reason I will open the comparisons up to some dynamic driver headphones as well.[/size]
[size=medium]
Mad Dog - This is the only other orthodynamic headphone that I've had the fortune to try so far. Although it's based on a much headphone costing 1/4 of the HE400, the external changes that Mr. Speakers have added to it (additional leather headband and new Alpha pads) make it feel infinitely more comfortable than the original, or indeed anything else around that price. In fact this is one of the nicest headphones I've worn and it clearly beats the much heavier HE400 in the comfort arena too. Apart from weight the big enemy of the HE400 is clamping force (which it probably needs to stay on your head), it's a little too tight. This is made worse by the ear-cushioning being rather hard, which being symmetrical doesn't hug the head nearly as nicely as the Mad Dog's 'Alpha' pads. So the HE400 doesn't seal quite as well, but being open-back it doesn't really need to and here we reach our next problem comparing the sound. The original Fostex T50rp was a semi-open headphone and it isolated reasonably well, but the Mad Dog modification has made it more like a closed-back. [/size]
[size=medium] The air and separation of the Mad Dog may not be quite as impressive as the HE400, but the soundstage is stunning with both. The tonality of the two presentations seem pretty similar, especially now that the Mad Dog is using the new Alpha pads, they're both a little on the warm side, but both manage a staggering lack of colouration into the mid-range, shine for vocals and have very well controlled upper ranges. Both headphones need nice, powerful amplification to flourish, but I would say that the HE400 comes out a bit ahead on pure versatility of sound quality (possibly more for Classical and Jazz) because of the few open-back qualities. If you find yourself sitting on the fence between these two headphones I would recommend mostly using the need of isolation to steer your decision.  [/size]
[size=medium]
Sennheiser HD650 - This is a classic, well balanced dynamic headphone and it's price is close to the HE-400 (£330 vs £400). Comfort wise the HD650 pretty much wins. Not only is it very light, but the ear-cushioning is fabric, which makes makes it a bit more comfortable and less hot. The HD650's clamping force is similar to the HE-400, a bit too much relative to weight, but since the weight isn't there it's less of an issue. Like the HE-400 the HD650 has dual entry removable cable, although the Sennheiser's push fit might be much easier to use it also seems more problematic under constant use. [/size]
[size=medium] So tonality wise the HE-400's sound seems to sit neatly between the Sennhseiser HD600 and the HD650. With the dynamics the more neutral HD600 seems to be what most audio enthusiasts & pros  prefer and I agree. The HE-400 is a little warmer than that, The upper bass has a substantial weight and kick to it, but it doesn't poison the mid-range as many lesser headphones do. By comparison, even the HD650 is a bit bloated for some music, although it's saved somewhat by being in the realms amplification tonality balancing, which is why I think it's loved so much. [/size]
[size=medium]
I wish I could say more about the Audeze range and how it compares here, but unfortunately I haven't had the chance to try them yet. Since the price is so far different from the HE-400 to the LCD-2 I'm too worried about this right now, if I get my hands on the HE-500 it will be more of an issue[/size]
[size=medium]

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[/size]
[size=medium]      BUILD[/size]
[size=medium] The HE400s are one of the most heavy headphones I've tried to date. This seems to be a theme with the orthodynamics from Hifiman and Audeze. In the Hifiman's defense there's a lot of heavy-duty metal in the construction. Actually the first bit of plastic you'll probably find is as you examine the cable terminals. Then there's the fake leather headband & ear cushions, but apart from maybe a couple of tiny washers (and perhaps the driver assembly itself) the rest is all metal. They feel very strong and the design is nicely simple, which at least seems like parts are easily replaceable. [/size]
[size=medium]
Speaking of removable & replaceable parts Hifiman have done a nice job with the cable. Yes, you expect a removable cable at this price (even if you don't always get one), but this screw fit, dual entry cable is a really nice touch. I guess if I was to nitpick I could say that it's a little fiddly to secure at times. A better grip on the screw mechanism and end of the cable, so you could hold both and twist more easily would be appreciated, but this really isn't that bad. The other end of the cable is terminated by a 3.5mm connector and it comes with a push on 6.35mm adapter. I would have preferred to see a 6.35mm connector here and an adapter for smaller jacks - a la Sennheiser HD650, again a very small nitpick. [/size]
[size=medium]
     COMFORT[/size]
[size=medium] The large space inside the ear-cushions makes for an almost perfect comfort for the ears themselves. The HE-400 might be described as a 'Lightweight' on the companies website, but it still weighs a hefty 440g. To better manage the pressure on the headband and stop the headphones from slipping down Hifiman have made the clamping force quite a bit above average and some people will find this annoying after a while. OK, it's not the most comfortable headphone in the world, but it's not that bad either. I wonder if a velour type ear-cup material could have softened the clamping pressure and lowered the ear temperature somewhat.[/size]
[size=medium]
     FINAL WORDS[/size]
[size=medium] OK, I have a couple of reservations about the HE-400s comfort, which I know I made sound worse than it really was, but overall there really isn't much to complain about with this headphone. I would still give comfort & fit an 8/10 score. [/size]
[size=medium] Overall I really love the HE-400 and I can't recommend it highly enough. If you can afford it and you like a generally balanced sound with impressive bass body then put them at the top of a small list. This is the cheapest high-end production orthodynamic headphone available at the moment, but it certainly doesn't seem like a cut-down model. It's also the cheapest one that I have tried, so I hope to try many more soon (stay tuned).[/size]
[size=medium]
If you can't stretch to this budget, but you like the idea of this sound then I highly recommend looking at the SoundMAGIC HP200. [/size]
[size=medium]

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[/size]
[size=medium]  [/size]
[size=medium]     EQUIPMENT USED[/size]
[size=medium]

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[/size]
[size=medium] Desktop PC, Dell Vosto Laptop, Samsung Galaxy Note 2, Audiolab M-DAC, Shonyun SH-306A, Schiit Modi & Magni, Epiphany Acoustics E-DAC, Benchmark DAC2 HGC, SoundMAGIC HP200, Beyerdynamic DT880 600 Ohm, AKG Q701, Sennheiser HD650, Sennheiser HD600, AKG Q701, Mad Dog (Fostex T50rp mod), Fostex TH600[/size]

The price to performance ratio of the HiFiMan HE-400 is truly exceptional. The clamping force of new head band is tight and requires break-in. I prefer the the plush pads over stock pads for comfort. Once HE-400 is broke in, like a pair of old boots...they become comfortable but not super comfy..due to the weight of these cans being on the heavier side. 
 
Equipment used for this review
 
HiFiMan HE-400
 
HiFiman HE-300
 
Grado GS1000e
 
Bose ae2
 
Decware Zen Head amp
 
Emmeline "The Black Bird" SR-71A amp
 
Schiit Valhalla 2 amp 
 
Modifies Play Station1 CD player
 
iPod classic 160gb
 
iPhone 4s
 
ALO Audio 30pin line out dock cable
 
AudioQuest cables
 
All tunes sourced at CD quality bitrate 1,411 kbps, iTunes, Tidal music player, CD's, WAV files
 
 
 
 
 

 

I've been wanting a bassy open headphone for a while and after a bunch of research I decided on the HE-400. I normally have no interest in high end headphones because they lack bass, but from what I've read the HE-400 will give me a decent amount.
This is a quick impression from a basshead's point of view since there's already plenty of reviews, but most reviews are from audiophile who don't normally use and listen to bassy headphones.
I used the new FiiO E12 (the no bass version) for this impression with flat EQ on my iPod video 5.5G.
I use this set up because I have multiple listening spot in my house.
 
Value:
Definitely worth the $400, I got mine from Justin @ headamp.com for $335 shipped, factor in the sound and build and it easily worth more than $400.... If you're an audiophile. For bassheads it would depend on how much bass you're looking for.
 
Audio Quality:
I love the sound of the HE-400 but I do wish there was a bit more rumble, but I wasn't expecting it since it's an open audiophile headphone. The sound quality wasn't the leap in sound I thought it was. It's better than what I previously had but it wasn't that much better it's more of a different better. To my ears the HE-400 kinda sound like the portapro (which I love btw) but better everything. The mids are great and highs are nicely details without piercing my ears like most audiophile headphones. Vocals are nice and clear. 
Now for the bass. It's good bass, clean, fast and just loud enough but no way is it basshead level.
For audiophiles who don't normally listen to bassy music or use basshead headphone will call the HE-400 bass heavy. For us basshead it's not even entry level. It's nice bass but lacking in quantity even with a bass boosting amp. The FiiO E12 with it's weak bass boost did not do much in uping the bass quantity. The quality of bass is great though.
 
Design:
I love the design of the HE-400, it easily one of the best looking headphone I've used. Build quality is solid too. The cord is the only issue I have, it's too long and too stiff.
 
Comfort:
I personally did not have any issue with comfort. I had mine on for 3 plus hours without any discomfort, but I don't normally have issues with uncomfortable headphones (except the V-Moda crossfade and Shure SRH750DJ) so take what you want from that. 
 
Overall:
I am a basshead but my demand for bass is not what it use to be. I don't want bass all the time, but when I'm in the mood for bass I want a lot of it. The HE-400 is good enough for normal listening session, but when I'm in the mood for some serious bass I usually skip the HE-400. When I first started here I got a lot of recommendation from audiophiles saying this and that has a lot of bass, but when I buy them they lack bass big time, I realized most audiophiles have a very different view on bass. What's lacking to bassheads are a lot to audiophiles. The HE-400 falls into this category.
Overall I'm happy with the HE-400. It sounds great and even though it's not basshead level, the bass is good enough.
I'm currently looking into other amp that will max out the HE-400 so I might update this later, but for now the E12 is not doing the job I bought it for so back it goes and will be replaced by the C5.
 
 
EDIT:
[02/20/2013] Today I decided to use my E07K, I max out the bass(10) and gain(12) and the HE-400 gave me a good rumble, but once I up the volume to about 40 (65%-70%) it started to distort. 
At least now I know the HE-400 can give me a bit more bass quantity with the right amp. The E07K is not the right amp, SQ suffers when using this amp.
I have come to a conclusion, this headphone will never truly satisfy a true basshead

First things first, there is a simple trick that solves all the complaints about the cable connectors - simply rotate each 720 degrees counterclockwise to build up some torque before you screw each one on clockwise.  Since you only need to screw 540 degrees clockwise to fasten them, the extra twist remaining in the cable keeps them securely fastened without having to overtighten.
 
The build is nothing special.  Yes the R/L markings rub off.  Also the screw placement is oddly asymmetrical.  Materials are not luxurious, and comfort is just average (though comfortable enough that I can enjoy them for hours on end without distraction).  They are somewhat heavy.
 
Bass is incredible.  In this price range, I am unaware of any headphones with this kind of bass extension, impact, and natural sound.
 
High mids are a bit recessed (less so with the velour pads), yet the mids as a whole remain clear, detailed, and vocals show great depth.
 
Speed, transparency, imaging: all strong suits.
 
These headphones absolutely shine with jazz, rap, electronic, funk, rock, and pop.

 
 
My take on these cans:

I've had the HE-400s for about year, and am now running them through a V-Dac II into a Burson soloist. 
Argon 5057 Cables between the amp and dac. My pair have the revision two casing (White-ish).

For modifications, I swapped pleathers for velours and removed the mesh that was glued onto the grills, no problems caused from that so far so thumbs up. It would probably be a safer bet to keep the hifimans under cover once in a while so they don't collect too much dust. These two mods are a must for anyone wanting to get the most out of these cans, however I wouldn't recommend the mesh mod if you have an already bright system as it slightly adds more treble and contributes to more fatigue (at least that's what I have observed). 

Genres I listen to: Metal of all kind, female vocals/acoustic, pop, dubstep & electronic. I can only comment on my own system because i've never owned anything else. The sound you get from these is very full, bass is perfect, prominent in the mix but not too much that it takes away from anything else, mids are really nice, gives guitar and vocals that extra richness. I have had to EQ the highs a tad, because these can get harsh with some less stelar recording mixes, Soundstage and imaging is good, you can pinpoint all the different elements in the song. One of the only negative things that I can find in the sound (and I may be over-emphasizing this) would be the really wide soundstage (more on the sides and less in the centre) that may make music that's played on a stage seem less realistic. This doesn't really bother me but if you're really looking for that speaker-like soundstage, other cans may do this better. This wide soundstage works perfect with more digital music like electronic etc.

The HE-400s build quality (driver casing/headband,etc) seems really durable, but these cans really need some refining. There are some things I feel could have been better, the 'Hifiman He-400's logo paint has started to fade, the R/L channels have completely dissapeared over and the cable has started to ware right before the connectors. Also, comfort is one of the big cons of this otherwise, really great sounding headphone, so take this into consideration (I am looking into upgrading to the revised models, HE-560).

What else can I say..I wouldn't say this headphone responds alot with better equipment, probably because of its efficiency. The V-Dac and Burson amp did make subtle changes but if you're budget is limited, going with less expensive options won't set you far away from the headphone's full potential. Only thing I would look into a headphone from this would be more detail, less brightness, more realistic imaging, and refinement in build and comfort.  I think synergy is pretty good, the Burson Soloist gives the HE-400's all the power it needs (does not need this much), and the Musical Fidelity Dac adds warmth so anyone looking at this setup, go for it. Conclusion: All rounder cans, great value and a nice step into the audiophile world. Feel free to message me about the headphones, dac or amp. and thanks for reading my review.

EDIT: Hifiman has released two new models, the HE-400i and the HE-560, these are discontinued.
 

Preface

The “low” end of the Hifiman classics that is recognized alongside the lineup of the legendary HE-500 and HE-6. You rarely see these on the used market nowadays since their release about 7 or so years ago (before I started even in the hobby). I’ve read posts from previous owners (and current owners) about the touted bass on these as being fun and enjoyable when compared against the HE-500, and does not reach the bass quality of the veneered HE-6 when powered through speaker taps. This made me really curious about the performance of these when compared against my HE-500 and was fortunate to purchase one recently at a good price.

I’ll skip over some sections given that this is a used, discontinued model; there isn't much to talk about with regards to other tangibles (i.e. packaging, accessories). When I got this, it had a broken original SMC to 3.5mm cable, had the stock velour pads, and the HD650 padding stuck on the headband (similar to my HE-500). With those out of the way, let’s get to the review.




Build and Comfort

Build quality is classic Hifiman; decent looking and heavy. There have been reports of this style of headband failing because the glue holding the headband sliders eventually weakens - I fortunately have yet to experience it on my HE-500, and this doesn’t seem to be the case with the HE-400 I bought used. So count me on the statistic of “still in working condition” Hifiman QC count.

I had the HE-400i that was released in 2016 with the suspension strap and on a personal note - I preferred that headband system because of the weight distribution being better compared to the singular band present in still current models like the HE-4XX and HE-5XX. That aside, the headband is reasonably comfortable overall… for the first couple of hours. After that, I feel a hotspot at the top of my head, which I attribute to poor weight distribution on this particular style of headband. I feel the same with the HE-500 and this weighs slightly less than that.

For the pads, the stock velour is just plainly irritating to my skin. It just passes what I consider to be comfortable. I’ll cover a short section about the sound when used with the stock velour, but I immediately replace it with the Dekoni Elite Velour for Audeze that I have and used for my HE-500 (currently in hibernation while I play around with other cans). How do the Dekonis feel? Predictably, much better and I’ve since then been using these as my pad of choice.


Amplification

These are rated with 92.5 dB sensitivity and 35 ohm impedance. This is neither demanding nor easily driven - about smack in the middle of having enough volume out of a decent source, but likely not enough headroom for highly dynamic tracks at louder than my preferred listening levels. They can run off an iPod just fine without me noticing any loss of quality. Heck, I don’t go past 9 o’clock on the JDS Element dial, and only go around 10 when EQ is applied. You don’t need a high wattage output amp for this based on my experience. Take that as you will as there are others who would slide in their comments about using speaker taps improving the bass and such - I am not one into trying that route so you can discuss with those individuals about them.

On a side note, for people’s reference, I usually listen anywhere between 60 dB - 75 dB.


Sound

As I mentioned in the comfort section, I did not find the stock velour very comfortable and instead chose to go with the Dekoni Elite Velour for Audeze. If you wanted a short summary of how the stock velour sounded to my ears, here’s the TL;DR: treble can be sibilant at times, bass has decent impact but texture feels lacking likely due to seal or decay and tends to bloom over midrange, midrange definition is overall good - however, it has peaks in weird places that makes some background instruments more noticeable at times and the vocals subdued, but at different parts of a song. I can’t explain it any better than that. But my takeaway is that stock velour has a weird V-shaped tonality. On a final note, there are those who claim that there has been a revision of the HE-400 at some point. I will say I cannot give more details on that and the different revisions as I didn’t look into it too much.

Since comfort and seal was an issue for me, I opted to go with the Elite Velours I used to have with the HE-500 - so essentially both my HE-400 and HE-500 are evaluated with the same pads (talk about consistency). The review moving forward consists of the HE-400 with the Dekoni Elite Velour for Audeze pads installed.

Further, I have not been able to find a reliable frequency graph measurement of these, so this will essentially become a completely subjective review without confirmation to my ears of what I hear. Guess this is the most subjective review I’ve written and you can put as much salt as you want with it, but I’m winging it so let’s go with it.

My music testing mostly involves modern tracks, OSTs, classic rock, 70s to 90s pop.


Overall Sound Signature

With the Elite Velours, the HE-400 is warm sounding, similar to the HE-500 but with some distinct differences (which we’ll touch later). The overall balance is decent in my opinion, bass comes across as warm, midrange has good definition, treble has enough energy to not make the tonality dull. I would classify this as warm-neutral with no EQ and is fairly enjoyable for modern tracks.

Bass

• Extension is good, but slightly behind the HE-500, rounding up to around 35Hz or a bit higher
• Bass is quick in attack, but texture is a bit unrefined, like they’re a bit loose. I think some would describe this as lacking “tightness”. This may have something to do with decay being slower compared to others I’ve heard. You can still distinguish the individual bass notes though
• Bass extends a bit to midrange, giving off a warm transition to the lower midrange
• Bass impact/slam is good, but I would have preferred more. Impact is a touch less than the HE-500 from recollection, and lesser than the Focal Clear I had before.

Midrange

• Lower midrange I feel has decent texture and definition. Male vocals have good quality and weight
• With the bass extending its transition to the lower midrange, this seems to add a layer of thickness to instruments like electric guitars, which makes them slightly incorrect sounding
• Upper midrange is a bit weird. Some notes are more prominent than others on certain tracks, which I find odd because other headphones don’t bring out such pieces in a song. Some brass or violin notes will come out with more volume than say the lead vocal at certain parts of a track, which I don’t experience with others like the Clear, DT1990, HE-500 and such. Not sure if this is what others would typically describe as ‘wonky’
• Piano notes have good texture and definition. *Some* female vocals seem to lack weight, while others sound fine
• Vocal transition is good, similar to the HE-500 and DT1990 in quality, but maybe just a touch slower and not as smooth in transition

Treble

• Treble air quality seems hindered a bit, like the 10kHz region is more subdued than preferred, adding to the overall warm tonality
• Presence region (6kHz - 8kHz) has enough energy to give liveliness in a song, but seems to have some lingering effect on the consonant range and some ringing effect of some sort
• This presence region makes some consonant ranges and cymbal crashes sound sharper than what I prefer, but it’s not in the level of annoyance as the Focal Clear or TH-X00
• Overall passable treble balance leaning towards the warm side with a slightly peaky presence region

Detail Retrieval (Resolution) and Dynamics

Overall good, but maybe a step behind against the HE-500 and DT1990 in stock tuning with the Elite Velour. There seems to be some weird peaks and dips in the midrange to upper-midrange section that’s causing some details to share the center stage with other instruments at different times. Once EQ’d, it fixes this unusual detail retrieval presentation to something that sounds more normal. With EQ, I would rate the detail retrieval and resolution only a half step behind the DT1990 and HE-500.

Dynamics is also a positive for me. Bass dynamics and slam are a bit behind the HE-500 IMO. Initial leading attack on the upper midrange to treble region seems somewhat blunted, likely caused by the weird midrange peaks it has. It’s just slightly dampened when compared against the HE-500 and I would attribute the cause to be from the weird upper-midrange to treble balance. Even with the good dynamics, cohesiveness of the different instrumental pieces are great and something that makes music listening engaging. Overall dynamics is still behind the Focal Clear to my ears, as I think Focal is still leading in this technicality.


Head stage and Imaging

Like my other reviews, I don’t give this technical ability too much notice since most of the songs I listen to don’t require me to concentrate on this aspect. I usually multitask when I’m listening, I don’t often listen to music just to listen. I will say that the head stage presentation is about average, stage width = average, imaging = no glaring flaw to speak of. It’s cohesive enough across the 180 degree listening stage for me.


Timbre

Overall, a bit coloured and lacking in naturalness to my ears. There is this weird dips in the upper-midrange that makes female vocals sound a bit odd at times. Further, there is this ‘plastic’ effect that is noticeable when the presence region is reached, namely in the consonant range. I suspect this comes to the decay of the drivers that’s hinting at a somewhat plastic sound after the initial consonant range is pronounced. (What I mean by plastic effect, imagine tapping a ziplock bag and the sound of that plastic crinkle - that’s the sort of sound I hear during the decay of the consonant range pronunciation).

Instruments like piano, acoustic and electric guitar sound tonally correct for the most part. What some of the instruments lack is that initial ‘bite’, which I will attribute to the combination of upper-midrange and treble balance.

In summary, it’s not as natural sounding as the HE-500 in stock form. However, it’s not overly coloured to the point that it sounds completely incorrect. It just adds some colouration that some might find enjoyable. I certainly enjoy this type of colouration on some songs, but not so for others. The thing is, if I don’t find it consistently correct in timbre on the majority of the well recorded tracks I listen to, I can’t give this particular category a good mark. Timbre quality is just on the passing line grade for me.


EQ

As always, EQ for the most part fixes the tonality section and some of the timbre issues. The midrange to treble balance has for the most part been alleviated for me. The ‘plastic’ decay quality in the consonant range has also been reduced significantly, so only a hint of it remains with the EQ profile I use. Bass has also reduced its uncontrolled texture and over-reach to the lower midrange. It’s still not quite as impactful as say a Focal Clear, but it’s more linear sounding which I prefer. This headphone takes a lot of EQ’ing to get to my target curve, but once it reaches my preferred signature, it has been pleasant to listen to.

Among the most interesting things about the HE-400 EQ’d and the HE-500 to my ears, is that it makes voices (especially female vocals) sound like they’re not coming from a set of speakers, nor does it sound like a playback recording. I can’t quite point to it, but there is this certain sense of texture in the vocal range that makes them sound like they’re right there with you, as if they are life-like in quality. Besides these two, the DT1990 EQ’d is similar in quality for this but maybe marginally behind. Of course, your findings may vary as our experiences differ. We tend to differ in what sound texture we look for that registers to our perception of what sounds real or not.

At this point in time, I’m EQ’ing almost any headphone I get nowadays. The only exceptions so far that I find doesn’t need EQ to sound great are the HE-500, HD600 and Focal Clear. For the HE-400, I am one to recommend EQ with them. This is not to say that they are un-listenable in stock form. No. You may like the stock tonality for sure, but to my ears, the stock tuning is not something I would openly recommend to the next headphone enthusiast.


Comparisons

Hifiman HE-500

How does it compare to it’s older brother? They share some characteristics (other than their design and build quality). In stock form, the HE-400 tonality is more V-shaped, while the HE-500 is more linear sounding. The HE-400 hits my sibilance sensitivities for certain tracks, whereas it is absent on the HE-500. The HE-500 has the better extension on both bass and treble to my ears on both ends than the HE-400.

With an EQ’d HE-400 vs HE-500, I can’t say yet. The HE-500 is in hibernation for the time being as I expect my perspective will change and have this particular guilt on why I keep trying out new headphones when this is close to my ideal signature overall. Both are discontinued anyway so it doesn’t matter too much since these come every so often in the used market. Still, I would say the HE-400 EQ’d is a good alternative if you can’t find the HE-500, and I find the HE-400 the more ‘fun’ sounding of the two.


Hifiman HE-400i (2016 2.5mm version)

I haven’t heard the HE-400i in a while, so I’m only going by memory of it’s overall tonality - bright neutral. There is a presence region shout that can become sibilant at times. I like the bass better on the 400, but I didn’t really play around with EQ on the 400i so I can’t say much about its potential other than the stock form bass is quite lean in texture despite being tight and quick typical of all the planars I’ve heard so far. Head stage width is also narrow on the 400i for some reason, it could be my unit is defective or my dac/amp setup at the time (E07k/E9) is causing problems with it.

Comfort also goes to the 400i with that suspension strap structure distributing weight better.


Sennheiser HD600

One of the iconics in the headphone world. As I’ve mentioned in the other sections, if someone is looking for a no-frills headphone that sounds great all around without needing to mess with any other DSP tools, the HD600 is the choice. It has an inoffensive tonality and good technical abilities, hence why it’s been recommended time and time again despite its flaws when compared to certain headphones people prefer that’s not a Sennheiser HD6X0 series.

When an EQ’d HE-400 is put up against the HD600, it becomes more competitive. With the profile I use for my target curve and earpads, the HE-400 I find is better in almost all fronts (except for comfort) by a small margin. It’s a bit more dynamic, a bit more engaging, with vocal qualities that so far is at the top of my list. Feel free to disagree, because that means we already differ in perspective, and I’ve mentioned on my section about Timbre that this (EQ’d) and the HE-500 have vocal qualities that I find special compared to the rest I’ve tried. I'm not with the majority that find the HD600 vocals to be realistic sounding, only tonally correct sounding (if this is what most would mean by 'natural' sounding).


Conclusion

For a discontinued model made around 2012, I feel this is one heck of a bargain at its used market price (<$150). Hifiman’s double-sided planar in the HE-400 and HE-500 have some special quality to them that I find isn’t quite captured in the newer HE-400i released in 2016. I can’t say if the newer Hifimans are able to replicate it, but from most that I’ve read around, it seems the Hifiman sound is a bit different nowadays. Better to ask others who have the OG 400 and the newer ones to compare it to.

I can wholeheartedly recommend the HE-400… if you meet majority of these criteria:

• Have strong neck muscles
• Confident in doing even simple mods on them (i.e. pad change)
• Likes a semblance of V-shaped open back tonality in stock form
• Use EQ to fix flaws in the signature
• Likes a ‘fun’ and ‘engaging’ pair, however you perceive a headphone as being those two adjectives

The stock tonality is just a pass for me, and is something you might want to hear for yourself. Stock velour pads become sibilant for a number of songs I listen to, so that is an off mark for me. Further, stock tonality is not very correct sounding to me. However, at the price they can be had at the used market for less than $150, I’d still put this on my list of ones to obtain.

Overall grade comes down to the following:

• Stock tonality - 7.3 / 10
• EQ’d tonality - 8.5 / 10
• Comfort - 7 / 10
• Technical Abilities - 8.2 / 10

Because of how good I find these when EQ’d, I will be giving them a score of 4 / 5 here. Excellent sonic performance with decent comfort at the market price gets a high mark from me.

Thanks for reading my lengthy write-up.

This is one of my few reviews, Im not a type of person to give reviews when buying an item but this time I had too. I was looking for a good setting to have a portable hifi system and I knew to achieve this its not coming for cheap but also I had a budget. After reading many reviews I decided to go for these planar headphones the Hifiman He-400 and also bought the Fiio X3 to drive them with.I was so excited when I received them that I couldn't wait to try them on. But to tell you the truth I wasn't that satisfied! Yes its true you will hear instuments and clearness that with my other equipments I couldn't but I love to listen music load and perhaps without losing from quality thats why I spend around 400 Euros for them but with Fiio X3 at full power wasn't so impressed. I thought that these headphones were not driven hard enough so I decided to go for an Amp. My choice was between C & C BH  -  Fiio E12   - Cayin C5. But finally I choose the Cayin C5 and theres were the magic begins. BANG it was amazing. This great Amp was helping the Fiio X3 driving these beefy Hifiman. With the boost turned on from my amp I could still enjoy a crystal clear quality and I couldn't believe the sound was coming out from this equipment and getting the best from these headphones. Finally I spend around 500 Euros but now I can say they were well spent

My source is a 2011 Macbook Pro-->Emotiva XDA-1-->Schiit Asgard-->HE-400
 
*Disclaimer* I have Jerpad 2.0 modded the headphones
 
The HE-400 does many things well, but the star of its presentation is the bass quality.  
It has very good slam for an open can, but its texturing is to die for! 
Cello sounds very realistic, with a roundness imparted by its bass extension.
 
In terms of the mids, male vocals have a very visceral, tactile quality about them, whereas female vocals seem to be missing a little bit.
 
The treble is rather hit or miss.  It seems to be fairly well extended, but it has a bit of tinny-nes and definitely sibilance that creep in from time to time.
I find electronic, rock, and vocal tracks to be the best for this, but then again I don't listen to many other things, so take this with a grain of salt.
 
To compare this with the HD800, which I have only heard twice in Bay Bloor Radio, the bass has better texture, but the mids are more "accurate" sounding on the HD800.
Of course, the soundstage/imaging on the HD800 trounces the HE-400, and the treble is far better extended on the HD800.
This is only from what I remember, and I believe the Sennheiser was hooked up to a Bryston amplifier.
 
All-in-all, I love the HE-400 for what it does best, just wish there was a bit more presence in the upper mids to make them a little flatter.

I have owned my HE-400 for over 3 years now. I have gone through a love hate relationship with them as they simply are not the jack of all trades headphone I was looking for. However, over the years I began to appreciate their outstanding qualities they do posses. These cans go incredibly good with trip hop, hip hop, instrumental and orchestra. Vocal based music is a hit or a miss. Males can end up sounding quite a bit deeper but sometimes missing that organic warmth due to the rise of the 1k region and scooped mids after which make vocals sound nasal. Same applies to women vocals, but that is caused by the peaky highs. Again this depends on the track and how it was mastered. Bright songs tend to be too peaky and the highs on this headphones do not pair well with that, warm mastered songs have no problems. However, movie soundtracks, movies themself, games, instrumentals and complex passages are fantastic. American music sounds fantastic too think of hip hop, rap or pop songs. Their imaging and soundstage are good for gaming too. These headphones have lightning fast transient response, and have a tremendous way of imaging the sound in this almost holographic fashion. They tend to still give me that surprise or waw moment even after all these years. They do sound better when around the 90db mark and not lower, but listen with care people. Also, make sure your room has no fridge or such in the background as any background sound messes with this headphone's clarity. They leak massive amount of sound so it's a headphone for private listening. All in all, these are definite keepers. They are so good for their price range that I decided to buy a second pair in case they become too rare over time. This headphone is a clear step above dynamic headphone offerings under 500$. Their achilles heel is that the stock frequency response is not for all tracks which is also why I will buy a HE-500 alongside these, comparisons will be made in the interest of time. If you are looking at Planar's look at the HE-6, HE-500 or these. The double sided magnet design give them a more organic and speaker like presentation that not even the newer planers from Hifiman can match.

 
As of September 2014, the HE-400 has been discontinued, and it's successor, the HE-400i is being sold in its place. So why publish, or even read, a review now? First, there are many used HE-400s in the market and are being considered for purchase. Second, many retailers still have new stock of the now heavily discounted HE-400, and these are the latest versions with no risk of future revisions. Third, based on 3 days of listening to the HE-400i, I've concluded that the new 'i' version is not an upgrade to the HE-400. It's a different sound signature. Asides from the considerable cost savings, I can see how someone could prefer the sound of the original HE-400 over the HE-400i.

Review set-up;
Source: PC  -> Teac UD-H01 USB DAC -> -or- FiiO X5->
-> Objective 2 Amplifier -> Hifiman HE-400 (Pleather Pads)

Hifiman HE-400

The Hifiman HE-400 is an open-back, over-the-ear headphone with an orthodynamic / planar magnetic driver. It's a break-through in the sense, in that Hifiman achieved it's relatively affordable pricing through advances made in automating the production of the traditionally handmade planar magnetic drivers. Most recent models with this type and size of driver are sold closer to the $900-1000 mark or higher when introduced (the prices come down of course). The HE-400s MSRP is $400, and (as of Sept. 2014) the fact that it's successor, the HE-400i (MSRP: $500) has hit the market, has a street price of significantly way below that.

With a rated sensitivity of 92.5 dB/mW at 35 Ohm impedance, it falls into the  category of high-efficiency planars - headphones with planar magnetic drivers that don't need a powerful desktop amplifier to sound their best. In comparison, the HE-500 and HE-6 models up the line have sensitivity ratings of 89 dB/mW and 83.5 dB/mW respectively. Since dB is a logarithmic unit, an 83.5 or 89 dB/mW sensitivity rating means a headphone will need a lot more power than one rated at 92.5 dB/mW to reach a given loudness level, despite what the  small difference in number would suggest. To reach the volume of a typical live concert (115 dB SPL),  the HE-400 will need ~177.93 milliwatts while the HE-500 and HE-6 will need ~398.34 and ~1413.29 milliwatts respectively. Big difference.

(Note: these numbers are approximate as there is some disparity between manufacturer spec sheet numbers and actual measurements.)

Because of this, high-efficiency planars are in a practically different league from their desktop bound siblings, as they can be used  in a portable rig.  Ideally,  a powerful portable rig, as it still needs a fair amount of power to reach really loud levels. While the popular FiiO X3 and X5 players using their internal amplifiers (which are quite powerful relative to other portable players) can drive the HE-400 to fairly loud levels on their respective high gain settings, it still doesn't sound as dynamic, most noticeably in terms of bass extension and impact, as when being driven by a separate portable amplifier. Think along the lines of the better portable amplifiers, such as the Objective 2 or FiiO E12. The sound impressions written here are based on the HE-400 being amplified by the Objective 2.

Sound Impressions

Have a look at the =3651&graphID[]=3241&graphID[]=353&scale=30]HE-400's frequency response curve, against the curves of the Hifiman HE-500 and Grado SR80i. Notice that there is a dip at the 2000-6000 hz frequencies, but then goes back up at around 7000 hz to a peak at 9000 hz. This is what gives the HE-400 it's somewhat unique sound signature. Vocals, guitar, piano - anything that falls between the 2000-6000 hz range is attenuated or sounds further away, with the details being masked by the other more prominent frequencies, while the peak at the 8-9 Khz range imparts some brightness to the resulting sound. Translated visually, its sound is like a dark rolling cloud with rich tonal variations from black to middle shades of grey, punctuated with bright (but not blinding) streaks of lightning which can actually be very satisfying, depending on the type of music being listened to.

Hifiman themselves have stated that it is tuned for a more 'American' (I take it this means emphasized bass) sound signature, as opposed to the more polite and neutral 'British' sound of the HE-500 next up in the line. The HE-400's bass does have a satisfying amount of slam while still retaining texture and clarity - its massive planar magnetic drivers characteristically being able to render and stop the sound very precisely (transient response). This, combined with the 8-9 Khz treble peak, gives the HE-400 sound signature a satisfying sense of dynamic contrast with a combination of hard-hitting bass on the low-end and some treble 'air' on the high-end, albeit with (or in a sense, because of) a recessed upper mid-range and lower treble.

If you like live recordings of rock bands like Soundgarden, Guns N' Roses or Evanescence, with the thunderous and deep rumbling combinations of drums and guitar bass, and like to listen loud but without any shrillness in the treble from shrieking/shouty vocals, snare drums, cymbals, or lead guitars, you will appreciate the HE-400. In comparison, the Grado SR80i, which is also considered great for rock music, would start sounding harsh or piercing due to emphasized treble frequencies, and have  less bass impact at the same loudness level. Between them, it comes down to a choice between the HE-400's bass slam with good transient response vs. the SR80i's mid-range presence and detailed treble emphasis.

On the other hand, when listening to some acoustic or 'unplugged' recordings which have so much vocal or instrumental richness and subtlety in the 2000-6000 Khz range,  I would prefer either the STAX SR-207 or, to a lesser degree, the Grado SR80i, which will bring those elements forward. While the HE-400 by no means sounds bad with this type of music (it's still better than most 'default' headphones), I would prefer a more intimate vocal presentation - it's a subtle difference that can nonetheless change the way a song is appreciated.

I emphasized the word 'some' earlier because it really depends on how the music was mastered. I have high-resolution 24-bit/96Khz recordings of acoustic jazz with female vocals purchased from E-Onkyo Music, which sound impressively life-like with this headphone. Granted, these are audiophile recordings meant for playback in more technically capable systems, and it goes to show that the way the music is recorded and mastered plays just as significant a role as its genre. For typical recordings of electronic dance music and live rock (not acoustic) sets, the HE-400 generally works well.

 

Conclusion

Sometimes it pays to be late in the game.  Due to a combination of technological developments and price drops due to newer models being introduced, the Hifiman HE-400  scores very high in the price/performance scale. This assumes that the HE-400’s sound signature works with the listener’s music and preferences.  The newer model HE-400i has a completely different sound signature that does not build on the original’s strengths, so calling it a direct upgrade would be somewhat misleading.  I would consider the HE-400i as more of a sidegrade – a different headphone with a sound signature that appeals  for different reasons.

While the older HE-400s sound signature may not be ideal for all musical genres or recordings, when the stars of sound signature, music , and listener preference  line-up, it’s brilliant.  Combined with the Objective 2, it is still very much worth considering for high-end sound, in a  transportable package

Setup 1: Win7 PC -> USB -> Modi -> PYST -> Magni
Setup 2: Win7 PC -> USB -> E10k
 
Summary
 
Disclaimer: this is my first review on Head-Fi and I fully declare that I know (nearly) nothing.  Please be kind.
 
Based on the reviews I read here and elsewhere, I chose to go with the HE400's for my quiet, at-home setup.  My primary listening material is electronic house, jazz, and swing, so I figured I'd go with a headphone that everyone described as "fun" and "interesting".  But as soon as I plugged them in I knew something was wrong.  The detail was phenomenal, the bass lovely and linear (and gets notably better with burn-in), and treble surprisingly clear.  But most men's voices, the low notes in women's voices, some cymbals, violas, and french horns all sounded like they were behind a velvet curtain.  On some recordings these headphones are truly spectacular, but almost half the time I found myself recoiling at the bizarre frequency response hole with which I was presented.  After some 20 hours of testing and listening I have decided that $300 headphones shouldn't make me go "ew", and have decided to return them and try some much-flatter HD-600's instead.
 
Physical Attributes
 
The packaging is simple but effective and got the 'phones to me without any kind of damage.
 
Instead of a rigid carrying case, like what I got with my Senny HD 380 Pro's, HiFiMan provides a simple velvet bag.  While this might be good for some gentle kinds of transport, there's no way I'd put these in my backpack or anything.
 
Although bright blue in some photos, in real-life mine had a nice, dark blue colour.  The cans themselves look quite nice, but the headband and its attachments are bargain-basement.
 
Comfort
 
Out of the box the HE400’s definitely have death grip.  Fortunately, the headband is somewhat bendable, so it’s quite easy to reshape it to lower clamp force.  For that matter, if you had some kind of head deformity you could probably bend it to work around that, too!
 
The ear cups are nice and deep and didn’t touch my sticky-outy ears at all.  My HE400’s came with both the pleather and velour pads, and I found that the velours were about 7mm thicker than the pleathers.  The cups themselves are very large.  While this might be good for some people, they were so big on my face that they touched my jawbone and forced my mouth open slightly!  When I think of listening fatigue I don’t often think of a sore jaw, but there you go.
 
While I didn’t find the cable to be hard to manage, one strange consequence of its rigidity was that it pulled my head down.  I found that the cable had such a hard time bending around things (like the arm of my listening chair) that it would pull my head towards where the cable was coiled, on the floor in my case.
 
Despite my whinging, the comfort isn’t that bad, say 7/10, but they’re not a forge-that-you-even-have-them-on headphone like my HD 380’s.  
 
Amplification
 
While it could be that there ‘phones weren’t burned in at all, I did find that my E10k DAC/Amp didn’t bring out the bass in the HE400.  Once I got them home and plugged them in to my Magni I noticed that bass had much more presence, without ever being boomy or overpowering.  Bass is noticeably absent without amplification, though, so don’t listen to the marketing and think that you’ll be fine driving these with an iPod.
 
Sound
 
The HE400’s do most things very well.  I put on Sting’s The Last Ship and couldn’t believe how good it sounded.  Sting sounded perfectly positioned in the sound stage, and the acoustical accompaniments were clear and detailed.  I sat there and listened to the whole album and thought I had found acoustic bliss.  Despite what most say, I found that a lot of classical music, especially Vivaldi, sounded great on these headphones, too.
 
But when I put on nearly anything else I thought of velvet, and too much of it.  The female vocalist from The Moleskins, for example, sounded like she was singing from 5 metres behind her band.  A viola, cello, or french horn soloist sound like they’re playing in a velvet-lined box, and some cymbals sound as though they’re not even on the same sound stage!
 
So what is causing this?  The 2,000 to 6,000 Hz frequency response hole.  If you bring up the FR for the HE400 on HeadRoom you’ll see it quite clearly.  In retrospect I should have known better, but I was expecting it to manifest differently.  Material that is recorded flat presents the hole quite clearly.  It’s only material that is recorded with those frequencies over-amped that sounds truly great to me on these headphones.  And that’s what was going on with the Sting and Vivaldi recordings that I liked.  On my Shure E2 IEMs (my favourite reference monitors to date) Sting sounds way too forward and Vivaldi harsh.  The FR hole in the HE400’s was simply flattening those out for me.  Unfortunately for the HE400’s, most recordings are between flat and laid-back, and the more laid-back the worse the recording sounds on them.
 
Conclusion
 
The HE400’s are great headphones for some recordings.  They have a velvety-smooth signature, great detail, and amazing channel separation.  But when I add up the frequency response hole and the comfort issues I experienced I have decided to return these headphones and try something else.
 
Would I buy these again?  Probably not.  If I were to go for some more orthodynamics I’d go with something with flatter tuning.  Still, this was a fun experiment and I get to exercise Amazon’s return policy, something I don’t do often.
 
Arriving next week: Sennheiser HD600’s.  At least on a graph, they seem much more attuned to my tastes.

Full video review below
 

Engineer's dream, but lacks any comfort.  3 month owner.  
 
Pros:
Sound Quality excellent -
      Lows - shame on you if you don't already know these are bassy.
      Mids - average sound quality.  limited range, but great detail.
      High - slightly 'punchy'/undetailed and a bit bright, but still great.
No sibilance - you get the point.
Aesthetics - easy on the eyes, great look.
 
Cons:
Weight - padding on headband wears out in a month.  It will hurt your head if you don't bend the medal headband to size accordingly.  It got to the point where I had to make a custom pad for the top of my head.
Ear cushions - synthetic leather can get quite hot.  I tend to sweat with any form of leather, so aftermarket ear cushions were a must.
Cable connection - this is the biggest design flaw of the headphone.  I had my 400's RMA's because the connection point between the headphone and cable broke off.  The actual cable sticks out of the bottom of the ear piece and rubs against your shoulders which is annoying for some.
 
Bottom Line: I researched for dozens of hours on different headphones and consistently heard these were the best in their class. Basically, if you are thinking about buying for sound and would be willing to sacrifice comfort then welcome to your new headphones.  If you have the money then I would recommend buying the 560's as after testing had much better mids.

These are warm but detailed. They are fun to listen to, like the other Hifiman products (I have a couple).
 
I enjoyed using them and got a HE560.
 
Will give them as a gift to somebody. They are nice open headphones for the price. I can expect they will enjoy them.
 
Still working after a year of use.

Hey guys!

I know this is hardly the first review of these to ever be posted and I'm pretty sure everyone has covered all of the bases by now, but I've decided to throw in my two cents as well.

Introduction:

This is my first review here, so please don't lynch me.

I've owned these for two years and they have a special place in my heart as that one gateway drug that led me, not only to planars, but also to the higher planes of audio... Or so I like to think. Things have changed in the past two years and if you are looking for a good value, open-back planar, this is still a decent choice, but you might want to just pick up the HE-400S, since it has many improvements over the original.

Build Quality:

Ok, so to get this understood right off the bat - the build quality is good. It is. High quality material was used, the headphones themselves are mostly metal, the headband itself is also metal with a leather exterior.

However the design is not great. So to re-iterate, we have high-quality components, which have not been put together in the most ingenious of ways.

While the headphone itself is very sturdy, it has its issues:
 

1. The metal support for the headband si connected to the metallic casing of the driver through a screw on each side of the driver's casing. Now, the problem with these screws is that they have an uncanny tendency to unscrew themselves, so you have to screw them back in, which is quite frustrating. You don't even need to move around too much for it to happen, but it does.

 

1. The cable connectors... Ah, the lovely, lovely Hifiman solution for cable connectors (thank God, they've changed these with the newer models). They're something similar to reverse coax connectors, but I'm not really sure what. Either way, as the metal headband support screws, these also unscrew all the time, which is very, very frustrating and very damaging to the cable, in the long run.
   
   This can easily damage the cable as you need to rotate it to screw it in. Sure, you can rotate it in the other sense to compensate for it, but most of the time you're not going to get roatate in the opposite direction exactly as much as it needs to be screwed in and that will cause tension in the cable, which, in time, will damage it. For example, my Canare 3m cable died after about one year of usage and I had to replace it with the Silver-coated OCC 3m cable from Head-Direct
    
2. Stock pads constrict the sound and are not very comfortable. I'm sure that many of you are quite familiar with the "pads change the sound" phenomenon and it's true. The stock pads seem to take out some of the depth of the sound, it's like there's a very, very thin layer of plastic between your ear and the headphone.
   
   Additionally I spoke about the comfort. I am somewhat biased towards velour pads, because I like them more, due to not having them stick to my ears after long listening session.
    
3. Another issue is the weight that so many planars have. The HE-400 weighs about 440g, that's a little more than Fostex's T20RP MK3, which weights 328g and the Oppo PM-2 which weighs 380g. Additionally, the Newer HE-400S only weighs 350g.
   
    
4. The headband is not self-adjustable. I know a lot of people don't have a problem with that, but I prefer those, because they usually adjust accordingly, so I don't end up moving them by mistake and then not having the proper fit on my head and wondering what's wrong for a while... I imagine not many people run into this problem, though.

 
 
Sound Quality:
 
Ok, now here's the most important of them all. The sound quality.

Setup: I'm currently using my desktop PC, using a Oehlbach XXL DAC Ultra connected via USB (32-bit, 192khz) into which I plug my HE-400 directly. I have also used them with a Creative Sound Blaster Zx and a Asus Xonar Essence STU, but I will just talk about how it sounds with the Oehlbach, because it is the most fresh in my mind.

I'm using Foobar2000 as my player and my files are mostly FLAC or WAV, but I've also thrown in the occasional mp3.

I listen to all types of music, so I decided that I'm going to "audition" them and present their capabilities using multiple genres. Some of the songs I used are:

Michael Jackson - Thriller
Aerosmith - Dude looks like a lady
Queen - Keep yourself alive
Disturbed - Indestructible
Jesse Cook - Mario takes a walk
Queen - Another one Bites the Dust
Nova Menco - Journey
Joe Satriani - Surfing with the Alien
Steve Vai - Earthquake Sky
George Benson - This Masquerade
Guns n' Roses - Nightrain
Diana Krall - Fly me to the moon
Lee Ritenour - Night Rhythms
Ola Gjeilo - Ubi Caritas
Funkadelic - Maggot Brain
Infected Mushroom - Heavyweight
Pink Floyd - Comfortably Numb
Christina Aguilera - Hurt
Frederic Chopin - Grand Valse Brilliante (Interpreted by Valentina Lisitsa)

The tracks which I found more relevant are in bold and I will provide an explanation of why I found them to be important to my listening impressions.

So, right as you start listening to these, you can hear the immense soundstage and detail retrieval, they are really great, especially if you come from a closed-back headphone. Which I did, I tried them right after work, where I use a AKG K66. Not much of a comparison, I know, but it makes the WOW factor all the more obvious.
 
Michael Jackson's Thriller is a big-time hit for me. I've always loved this song, ever since I was little, but hearing it on a pair of HE-400 is completely different than hearing it on... Say, my old NEI television set, on MTV. I love this song and I listen to it when I try out headphones because of the great imaging and spaciousness it provides. From the start, when the synth and bass come in, you can tell that everything has taken its rightful place, being set just where they're supposed to be, offering a beautiful, beautiful imaging. It's not just once I've found myself pausing after the howling of the wolves, wondering what my neighbor's dogs are doing and why they're going nuts... Then I just realize that it's my music.

Aerosmith's Dude looks like a lady I use due to it's intermittent stereo sequence at that start. I generally blast the volume really high and see if there is any noise coming in between the guitar segments, in the quiet passages. While I did hear some noise, I later found out that the matter lies with my Oehlbach, not with my HE-400.
 
Queen's Keep yourself alive is a great song to show off the nice, smooth mids and incredible detail retrieval of this headphone. As soon as the song starts, you hear the guitar. You hear the pick strumming the guitar strings. You hear the edge of the pick grinding against the edges of the thicker strings' exterior metallic wrapping. It's fantastic to hear this much detail and it is quite soothing.

Indestructible, by Disturbed is, by far, my favorite workout sound... But as you can imagine, I don't really go to the gym with my HE-400, I simply enjoy the song at home, sometimes and that truly isn't difficult to achieve, as the HE-400 brings a great bang and slam with its bass, as soon as the instruments kick in. You can feel their "raw power" and their energy right off the bat, but sometimes it gets a bit too harsh (more on that later).

Another one bites the dust, by queen, I find to be a great tool for listening to bass and sub-bass and boy, does this headphone shine here. The bass is nicely balanced and controlled, without being bloated or feeling artificial in any way. It has depth and it packs quite the punch. It's full and it's not the type of fatiguing bass I've seen with some very V-shaped response headphones. I truly enjoyed it, despite being more inclined to a more mid-centric orientation.
 
Earthquake Sky is on this list because you can easily hear the nice slam of the drums, which really puts the lower range of these headphones to value.

Nightrain is just on this list because it's my favorite song of all time and it proves that, even though I love Slash a lot as a guitarist, Izzy Strandlin was quite under-rated and its that specific underdog effect that makes the first solo of Nightrain my favorite guitar solo of all time... Also the highs sounded harsh and edgy. That was unfortunate, this is one of the few times in which the high quality version of the recording was a poorer experience to me than the low quality mp3.

Funkadelic's Maggot Brain is a song I got into when I was in high school, just learning guitar. This is also one of the first lengthy solos I have ever learned, so it's quite special to me. Half of it sounds as smooth as a summer lake at dawn, really showing how the mids are well-balanced within the whole sound, showing off a very detailed sound. As for the other half, the higher-end of it all, it sound abrasive, if felt like sandpaper was being rubbed somewhere close to my ears, at times.
 
Infected Mushroom's Heavyweight is good as it takes you through so many sound, building a complex imagery around you, showing you how well individualized this headphone makes everything, giving proper air between each instrument and having everything settle in just right.
 
Christina Aguilera's Hurt, now that's a song I really enjoy and its depth gives me goosebumps every time. It's about regret, it's about not saying what you were supposed to, what you wanted to, at the right time, it's about missing out on important things in life, like family and the loss of a loved one and also about the difficulty to move on after such a tragedy, it's about... Those damn high peaks that ruin everything. There are seriously some weird high spikes in the upper range of the spectrum which can be heard throughout the song. There is also some slight sibilance and just a general sense of unwanted edginess and this time the fault is not with my Oehlbach, nor was it with my Creative X-fi Xtreme Music, nor with the STU...
 
This, my friends, was the biggest flaw in sound quality I found with the HE-400. It can be partially resolved by equalizing the headphones somewhere between the 9-11k, but nobody really wants to do that. Nobody wants to spend a lot of money for a headphone in order to make it sound right. Of course, I'm not saying it sounds bad, but flaws like this can be quite bothersome, especially when they're so obvious in songs you really enjoy.
 
Additional Notes:

They're easier to drive than most planars, but I wouldn't recommend using them on your phone.
They're not portable and are not meant to be, they don't fold, they're not closed-back, they don't have a carrying case/pouch.
The HE-400 can be used as a small, mono speaker if you have a powerful enough amp.
Hifiman HE-400 are moddable, they can be modded in many different ways in order to tweak either sound or comfort. I have not tried any of these mods, all I have done is change the pads on mine and I'm happy with the result.
They come in a cardboard box, with a plastic support, but I don't care since I don't want to pay a premium for the packaging anyway.
 
Conclusion:
 
These are a beautiful way to into things, whether it is high fidelity audio, planar magnetic headphones or just another plane within the Nirvana of good music. Sure, they're a bit clunky, a bit uncomfortable, but they provide great value for the money. The sound quality is great, but it could be a bit better. They'll always provide a good experience, but most of the time they'll provide a great one.
 
Within the context they were released in, all those years ago, I would give them four stars, but now with the existence of the much better, many-times-over improved 400S, I give them  three stars. Mounting that up to an average of three and a half stars, which I think is fair.

Apologies if I forgot to mention anything (I'm writing this while at work, don't tell my boss!), I will update if I find it necessary and may return to post some pictures of the headphones.

Thanks for reading, let me know if you have any question (though I doubt it, at this point).
 

First of all, I was not running these from appropriate amplification at the time (Audigy 2 ZS Platinum Pro breakout box). Secondly, I have exchanged these for some other phones, and have only had them for a few days (also potential defects). Third, I am relatively new to the hifi scene. Therefore I have deemed it fair to give them 3.5 stars in order to not ruin the average. I felt I had to after that guy gave 1/5 stars for some reason.
 
With that out of the way, onto the review.
 
EDIT: Please ignore the scales to the left, they do not reflect what I think. I can't change them for some reason.
 
Audio path:
FLAC 44.1 16-bit or MP3 V0/320, various genres -> JRiver Media Center -> ASIO -> Audigy 2 ZS -> Platinum Pro breakout box -> HE-400
 
Previous phones i've owned are the Sennheiser HD202 (broken, piece of crap) and HD555's with the foam mod. I had the former for about a year and the latter for 3 or so.
 
Design / Build

1. These are Revision 2's.
2. Personally, I think these look fantastic. They are how I would design headphones if given the opportunity. It reminds me of something like a sleek old muscle car with a modern facelift. The colour may look showy to some in photos, but in real life it's not quite the case. It's a nice, dark shade of indigo blue that doesn't look gaudy at all. In fact, they look much more attractive and unique than the HE-500's with its boring grey scheme.
3. The housing appears to be some cheapish plastic, unfortunately. The paint job seems decent though.
4. The mesh can be removed fairly easily by pulling out a plastic retaining ring with your fingernails. This adds some nice modding options (diamond/criss-cross grills anyone?) that can potentially affect the sound. You could probably paint the ring to give the phones some accents too.

1. Apparently both drivers are wired in reverse polarity (I couldn't confirm this because I didn't have a mic). A few people argue that it has a negative effect though I can't say for certain.
2. Cable is removable, though uses unusual mini coax connectors for the drivers. I guess they used them instead of mini XLR for cost reasons.
3. Stock cable is not horrible as everyone makes it out to be (coming from HD555's, anyway). Bit too long and stiff though.
4. I feel that the connectors detract from the aesthethics (and function) however, and they should simply be sticking straight out the bottom of the housing; instead of being recessed (makes it more difficult to screw on the cables as well).
5. Earpads are a bit fiddly to put on, and they spin freely (not a big deal).
6. The round things with Hifiman logos that hold the arms for the housings seem to do a decent job of retaining its position.
7. On a whole, these don't feel or look like cheap headphones. They seem like they would take much more of a beating than the dynamics i've owned, and I don't see anything that would crack in everyday use (unlike the HD202 and HD555's). Not sure how they would cope being dropped onto a hard floor from waist height however.

 
Comfort / Fit

1. Repeating the words of everyone else, they are heavy. But when I first took them out of the box, they weren't as heavy as I thought they'd be.
2. Weight only posed a problem in regards to pressure on the top of my skull. It was probably the most annoying thing comfort-wise about these. I never experienced any kind of neck pain.
3. Headband padding is some faux leather and way too thin for my liking, especially with the weight of these. It was somewhat more bearable when I ripped the pleather padding off my dead HD202's and stuck them on though
   
4. Included earpads (pleather) are not as soft as i'd like and made my ears hot fairly quickly. The optional Hifiman velour pads were actually stiffer than the pleather ones (???) and definitely not up to scratch to my HD555's stock earpads, but at least my ears didn't get too hot. Overall, they did improve the comfort noticeably though (and sounded a bit better too).
5. It's possible to mount earcups from other manufacturers on. I've seen people mount Lawton Audio slanted leather cups and they look awesome.
6. You can bend the headband to fit your head better (manual says so), though I felt no need to do so.
7. All in all, actually not as uncomfortable as some people make it out to be. But I am constantly reminded of its presence, which detracts from the listening experience sometimes.

 
Sound

1. This is probably the part of the review I feel the most uncomfortable with as a budding headphone enthusiast. Bear with me. Also note that they probably weren't amped properly.
2. I was excited, so when I first got these I soon plugged them into the only source I had my hands on at the time: Galaxy S II (with varying genres of FLAC files running through PowerAmp player). I did not expect anything amazing at all. And I got exactly that. Nothing to speak of. I could only just barely get them loud enough at max volume. To be expected of a phone, even though HiFiMAN says it's good enough for portable devices.
3. I immediately plugged them into my Audigy 2 upon arriving home and started playing my favourite track: Give Life Back To Music by Daft Punk. I wasn't blown away, though I wasn't really expecting to be. I wasn't blown away when I went from my HD202's to HD555's either though.
4. I then started to play some ambient music (stuff like Jonn Serrie, Steve Roach) because I wanted an idea of how immersive it could be. Wasn't blown away here either, but I noticed the soundstage seemed noticeably wider than my 555's, though the depth was about the same I think.
5. Deadmau5 - I Remember - to test the bass impact and vocals. First of all, I am not a basshead. I was actually quite surprised here. When I heard the pulsating bass, it was strange, but not in a bad way at all. It sounded very much like a subwoofer, yet I felt no rumbling at my feet. I actually went to check if I accidentally turned my 2.1 set on. Still, they could have used a touch more bass quantity, though amping them properly probably would have done the trick. As for the vocals, they seemed less than impressive to me. They didn't really stand out and sounded a bit hollow to my ears.
6. I enjoy some classical here and there. Played some woodwind stuff. Problem: Certain notes were quite uncomfortable to listen to, I blame the treble spike.
7. I tested the bass further by doing some frequency sweeps within 20-200hz. The bass extension was truly something to behold. It really was like having a subwoofer mounted to your head (minus the physical rumbling).
8. Throughout all that, I experimented with various angles and distances between the drivers and my ears. A couple of things to note: there was significantly more bass quantity when I held them about 2cm away from my ears. Slanting them inwards (like on the Audeze LCD-2) seemed to reduce the 'nasal' tone significantly and make them sound more speaker-like. In short, they are quite sensitive to positioning compared to most dynamic phones.
9. Played some games, namely Mirror's Edge and Battlefield 3. Things like gunshots and explosions sounded lacking and hollow compared to my 555's, also I didn't feel as if anything took advantage of the bass extension. Then I wondered why the sound positioning didn't seem as good as the Sennheisers. Sounds coming from the front did not sound like they were quite in the center for some reason. I concluded that they weren't suitable for this purpose and I simply went back to my 555's for gaming.
10. Watched some video reviews on YouTube for a bit. Voices didn't sound right. I then swapped over to the 555's. It sounded like it was in the center as it should. I was confused. Played some movies to triple check. Same problem. I was worried. I posted about it on Reddit, someone believed it was a driver mismatch issue.

1. At this point I noticed my ears were tired and ringing more than usual (already had tinnitus). I didn't have them much louder than I usually have the 555's yet it fatigued my ears far more for some reason.
2. I'm not sure what to think of burn in yet, but I left them burning in on my desk in a cardboard box at slightly higher than normal listening level for about half a day. No idea if it made a difference soundwise. But during the time I felt that familiar fatigue in my ears. I feel there's some kind of resonance or something that I can't put my finger on, causing strain to my ears. This was probably the biggest problem I had with these, with the sound positioning issue following very closely behind.

 
Conclusion
I really wanted to enjoy these. They are aesthetically pleasing and I was very excited about diving into the world of planar magnetics. Unfortunately, quality control issues and a bizarre fatigue problem ultimately stopped me from enjoying them. That aside, and truth to be told - most of what is going to be coming out of headphones for me isn't music, as much as I am very enthusiastic about the stuff. I want general purpose headphones for computer/entertainment use that is decent at everything - music, gaming, TV shows and film.
 
I think I would have kept these if I had a dedicated listening setup for music. Heck, I don't even have a headphone amp yet. I have since replaced them with DT880's (Premium 600ohms, yes I need an amp, just trying to be future-proof here). I think they are a step up from the HD555's in every way for what I use them for. However, I do miss the HE-400's in a lot of ways. They provided a speaker-like experience. They sounded full and allowed you to feel the music, and just had this charm about them I can't put into words.
 
Would I recommend these headphones still? Yes. These issues might not even bother you at all.
It almost ticks all the boxes, but just misses a couple of critical ones for me.
I eagerly await a successor so I can give HiFiMAN another fair go.
 
I hope this review, though somewhat unrefined, helps people.

sorry my English is Google translate

The sound of these hifiman immediately like it or hate it.
They have a strong character, perfect bass, brilliant highs, medium tone mind incorrect.
A few years ago I was involved with live recordings of classical music and I used the stax lamda pro (magic but delicate) and Sennheiser HD 600 (less magical but tonally correct) as monitor of post production.
After so many years I decided to try this hifiman hoping it was a mix between strax and Sennheiser.
Ok I was wrong, hifiman has a different sound.
For two weeks I sailed between Acdc, metal, in exaggerated volumes.
Then I got the Audio Gd NFB 28 and headphones were taken off, especially in balanced.
Too bad the rest of the music I was interested less than usual, then I realized that the particular signature sound port to listen at high volume that kind of music.
Loreena McKennitt's not good! His voice changes tone is darker, the musical instruments that are riding the midrange suffer.



Il suono di queste hifiman piace subito o lo si odia.
Hanno un carattere forte, bassi perfetti, alti brillanti, medi timbrica mente scorretti.
Qualche anno fa mi occupavo di registrazioni live di musica classica e usavo delle stax lamda pro ( magiche ma delicate) e sennheiser hd 600 ( meno magiche ma timbricamente corrette ) come monitor di post produzione.
Dopo tanti anni ho deciso di provare questa hifiman sperando fosse un mix tra le strax e le Sennheiser.
Ok ho sbagliato, hifiman ha un suono diverso.
Per due settimane ho navigato tra Acdc, metallica, a volumi esagerati.
Poi mi è arrivato l'Audio Gd Nfb 28 e le cuffie hanno preso il volo, soprattutto in bilanciato.
Peccato che il resto della musica mi interessasse meno del solito, poi ho capito che la particolare firma sonora porta ad ascoltare a volumi alti quel genere di musica.
Loreena McKennit Non va bene! La sua voce cambia tono, è più cupa, gli strumenti musicali che sono a cavallo della gamma media soffrono.

Recently i received a new set of HE-400s and took them for a spin.
I never made it past the first lap, so its time for the review.
I found their sound to be a combination of overly flat mids and spiky distant trebles awash in a sea of syrupy bloated
bass response with a touch of darkness throne in to hide any hint of presence or clarity.
I use a Woo Audio Fireflies and a ResonEssence Concero HP and a Maxxed out version of the discontinued Headroom Max as my sources, so, im not under-powering the HE-400s.
If you prefer overly flat mids and thick bass, then these are your best buy.
On a positive note, as i define the HE-400s sound as bassy with muddy mids, , they can also be described
as lush, rich, incredibly thick and wide, and very very warm......like a bear hug of low mids around your ears.
Sound-stage is impressive.
One thing is for certain, after you use the HE-400s for a while then change to any other headphones you own, your other headphones will ALL sound smaller.
Much smaller.
So, consider that as the other impressive caveat that the HE-400s can truly offer you along with the very nice sound-staging.
Do they sound bad?......No, not at all.......they just sound thick, flat, and wide.
Another way to think of their sound is if tubes in a headphone amp are very old and worn out and soft sounding..., that would be a way of describing the sound of the HE-400s...... very soft, very smooth, very round, very old analog.
You keep thinking, "wow, these could be so great if i could just add some upper mids and some treble".
And somehow the HE-400s are able to make their flatish - thickish- soft and round type of EQ tonality work, ,,,but that does not mean you have to like it.
I suspect that as these phones need power to make them speak, that many of the reviews you read whereby they are described as "bright" or "shrill" can be explained by the user trying to power these with an Iphone or some similar type device
which is starving the HE-400s and in that state they are going to sound brittle, especially at the top end.
However, if you give them the power they need and crave so that they can produce as they should, then you are will discover that they sound quite buttery smooth and very warm and thick and dark.
I like them, and i appreciate their sound, but my particular need is for more clarity in the mids and upper mids so that the music does not sound laid back and creamy smooth.
The HE-400s are nice cans, and worth the money, but be certain you are looking for their sound, which is nothing at all like a set of good dynamic open back headphones like the wonderful Sony MDR -MA900s.

Positives - clean extended, balanced bass. Lacks the physicality of an LCD-2, but that's not unexpected.
 
These are large, heavy headphones, that I found surprisingly comfortable to wear  when used with the velour pads. As reference, I have a small head, am not particularly sensitive to pressure on the top of my head, but am quite sensitive to pressure around the ear. For me, these were way more comfortable than I expected based on experience.
 
Build quality of the headphones seemed good - stock cable cover (not the cable itself)  was already separating at the Y junction however (purely cosmetic impact but not a good thing).
 
These headphones seem to be generally well regarded, but for me there was one factor that made them unusable - the treble. Fair disclosure - I am not a fan of overly bright treble, however with the HE-400 something beyond simple brightness was happening - almost a resonance effect in the highs. The impact for me was that listening to the HE-400s for extended periods made my ears hurt (beyond simple fatigue).
 
In some other posts, I have read about "tizzy treble" being tamed by carefully tightening the headphone cable connectors (which have a PITA design). This could have been my issue, but if it was it's certainly a design flaw. I could have had a bad unit, or my unit may have sounded as designed - I don't know. I do know that I could not listen to them for extended periods of time.
 
These were known good HE-400s without previously discussed (and now long corrected) build issues.