Pros: Good, smooth, reasonably balanced sound with many ergonomic improvements over HE-400.
Cons: Lacks low end weight, top end sparkle, holographic soundstage, and scalability compared to HE400.
INTRODUCTION
The HE400S is HiFiMan's latest offering in the HE400 series of open-back over-ear planar headphones. I first read about them in a teaser email HiFiMan sent out and was intrigued. I'd already read about the HE400i but didn't think it was what I was looking for. The HE400S however looked pretty interesting as an entry-level, easy to drive planar. The concept isn't new. Oppo's planars are also easy to drive. I've tested out the PM-2, but it wasn't what I was looking for, either. So what am I looking for? Well, I'm looking for something along the lines of my HE400 but with improved ergonomics and more even top end. Those two things (improved ergonomics + more even top end) would sell me a new HiFiMan HE400 series headphone. Is HE400S that headphone? Nope, it's not. It's a much more conventional sound signature than the HE400. Does that make the HE400S untenable for me? Perhaps, but I'd like to take some time to explain to you, as a dedicated HE400 fan, what I liked and what could be improved about the HE-400S. I hope it's useful for those of you looking to purchase a new headphone and are considering the HE400S.
Before I get started with the review, I'd like to provide a few links and encourage you to read over the other HE400S reviews on Head-Fi for alternative points of view.
HiFiMan HE400S page: LINK.
Headfonia review: LINK.
Dedicated HE400S thread: LINK.
DISCLAIMER
There is no financial incentive from HiFiMan for writing this review. I am in no way affiliated with HiFiMan, and this is my honest opinion of the HE400S. I would like to thank HiFiMan for giving me a chance to test drive the HE400S, and I hope my feedback proves useful for my fellow Head-Fi members as well as for HiFiMan.
ABOUT ME
I'm a 43 year old music lover who listens to a wide variety of genres and artists (but mostly electronic, metal, and modern composition these days). As with a lot of people my age, I've got some hearing issues - some upper frequency loss and mild tinnitus. My portable music journey started with the venerable Sony Cassette Walkman and then progressed to portable CD players, minidisc recorders, and finally on to DAPs like the Rio Karma, iRiver IHP-120, iPod, iPhone, and the newer crop of DAPs from Fiio and iBasso. My headphone journey started with Sony MDR e888 and Eggos back in my minidisc days. I moved on to full-size Beyerdynamic and Ultrasone cans and Shure E2 and E3 IEM. Those all served me well for quite some time. Then I rediscovered Head-Fi, and my poor wallet...
SPECS
Frequency Response : 20Hz – 35KHz
Sensitivity : 98dB
Impedance : 22 Ohms
Weight : 350g
Cable Length : 1.5 m
Plug : 3.5mm L-type plug
PACKAGING & ACCESSORIES
I'll let the packaging speak for itself. Let's just say that compared to when I purchased my HE-400, HiFiMan has stepped up their game considerably!
Open the box, and you see the HE400S looking up at you.
Open up the small black paper box at the bottom of the package, and you'll find the cable and a 1/4" adapter (not pictured). Since HiFiMan is marketing this as an easy to drive, portable headphone, the plug is L-shaped and small enough to fit into the rather small headphone jack opening in my iPhone's case.
Ok, that was pretty simple. As mentioned above, compared to the HiFiMan packaging for the original HE400, this is miles ahead. HiFiMan really stepped up their game here.
Accessories are sparse, but what more do you really need? A case, maybe? Not at this price point. HiFiMan will sell you one at a reasonable price, though.
BUILD & ERGONOMICS
Here, I'm going to present some pics comparing the original HE400 to the HE400S and point out my likes and dislikes.
First off, I find the HE400S to be a very attractive headphone in general but especially in comparison to the HE400.
I'm not using the stock HiFiMan cable, because it came in an ungodly length, so I got an aftermarket OFC cable that is a much more reasonable length. It's basically the same length as the HE400S cable, so for me HiFiMan nailed it with HE400S cable length.
The coaxial-type connectors used on the HE400 are a pain to attach. I much prefer the standard headphone jack type connector used on the HE400S. Also, please notice that the connectors on the HE400 come straight down out of the cup, whereas the HE400S connectors come out at an angle. I prefer the HE400S's implementation, which allows the cables to fall away from shoulders instead of straight down onto them as with my HE400.
Final thing to point out in the picture above is that there are defined headband adjustments in the HE400S, whereas the HE400's headband slides freely. I prefer the HE400's implementation, as I constantly find myself needing to adjust to 3 clicks on one side and 4 clicks on the other with the HE400S. That makes it feel just slightly off-balance to me. Nothing egregious - just a slight bit off.
Let's drill down a bit further into the headband and cups. The HE400's headband was never that comfortable for me. As you can see, I modded it with a Sennheiser headband pad. This makes HE400 more comfortable but dramatically limits how much I can adjust the headband. In fact, as you can see I need the headband adjusted to almost full height vs. under half the usable height with the HE400S. The HE400S's suspension headband on the other hand, is much more comfortable. It was a breath of fresh air coming from the HE400.
The HE400's metal cups and double-sided drivers make them quite heavy, whereas the HE400S's plastic cups and single-sided drivers make them feel feather light in comparison. Again, this adds tremendously to the HE400S's increased comfort over his older brother.
The HE400's velour pads are much stiffer than the HE400S's. The HE400S's pads are also angled, which allows them to better fit the contour of your head. Anther ergonomic win for the HE400S.
Last thing is that you might notice is that the L/R markings are completely worn off my HE400. I slapped on a couple pieces of lab tape with the L/R markings on them.
To sum up this section, there are many ergonomic improvements implemented in the HE400S that make it an easy win with respect to comfort over the older HE400. I joked in the HE400S thread that I was glad HiFiMan modernized the HE400 series, because the HE400 was starting to feel like a Cold War relic.
As mentioned above, I've also tried out the Oppo PM-2 open planars. I found the HE400S to have superior ergonomics, much preferring the HE400S's suspension headband and spacious cups. In comparison, the PM-2 feel crowded. I've got a relatively small head, so I can't imagine how people with larger heads squeeze into the PM-2 without serious comfort and heat issues during long-term listening sessions. No such problems with the HE400S. Of course, YMMV.
SOUND
I'm going to keep this section simple. Other reviewers have done a superb job describing the sound, so if you need further clarification or prefer a deep dive please refer to their reviews.
I mainly listen to experimental electronic and metal and use those genres to evaluate HP & IEM. During my time with the HE400S, I used them with my iPhone, as well as various DAPs and amps. I didn't find these scaled as well as my HE400, so while you're better off with a DAP or amp it's not necessary like it is with my HE400. With that out of the way, how do the HE400S sound?
I'm not going to say anything that reinvents the wheel here. If you've read some of the other reviews or been on the HE400S thread, you've probably gathered that they're a pretty conventional mid-centric sound that lacks a bit in extension on either side. It's a nice, smooth listening experience that won't easily offend anyone. So, if you're looking for a more conventional sound signature in a planar, then these might be right up your alley.
My 2yo son rocking' some Music Together with the HE400S :L3000:
In comparison with the Oppo PM-2, with the gear I used the HE400S sound fairly similar but with an improved soundstage and at a lower price point. This is from memory, so add a grain of salt, please.
In comparison with my HE400, the HE400S just can't match the HE400's full, rich, warm and impactful low end, the HE400's sparkle up top, or the HE400's holographic soundstage. However, the HE400S makes up for it with a much more prominent midrange and a distinct lack of treble spikes.
Still rocking' the Music Together but now with HE400. Doesn't look quite as happy this time, does he? Might be those Cold War ergonomics coming into play :wink_face:
SUMMARY
So what do I think of the HE400S? If I didn't have the original HE400, I think I'd be tempted to purchase a pair of HE400S. They've got a nice conventional sound, are very comfortable, and look great. However, being intimately familiar with the HE400, I'm left wanting more of that unique character that makes the original HE400 a special, if controversial, pair of headphones. In this reviewer's opinion, it would behoove HiFiMan to consider bringing a headphone to market with HE400's basic sound signature but with a more even top end and the modernized design and ergonomics of the HE400S. That's a headphone I'm ready to buy! Now!!! Please!!!!!
Again, I'd like to thank HiFiMan for providing a pair of HE400S for review. I thoroughly enjoyed my time with them and look forward to future offerings from HiFiMan and hope to try their mid and upper tier planars at some point.