Intro
The HE-400i is the latest headphone from Hifiman. It was released recently as a replacement for the popular HE-400. This write-up will give my initial impressions of the HE-400i as well as compare it to its predecessor.

I received my pair straight from Hifiman for reviewing and demoing purposes, here are my unboxing pics: http://imgur.com/a/04xke

Disclaimer: the last picture shows some kind of ink or colour on my hands. I thoroughly checked the headphones, contents, box, and packaging. I couldn’t pinpoint where it came from exactly. So let’s assume it wasn’t from the unboxing.

Presentation and Build Quality
The HE-400i came packaged in a nice leather box with foam insides. A huge step up from the cardboard and cheap plastic packaging of the HE-400. The only accessories included were the cable and the 1/8 to 1/4 adaptor. The cable is of a rigid fabric material. It is generally well-built and the cable itself isn’t too rigid. Much more flexible and a tad thinner than the black Canare cable included with the original HE-400. One thing that confused me about the cable is that it is very short – around 5 feet. Another thing that confused me was that it was terminated in an angled (90 degree) jack. Why is Hifiman including a short, 90 degree angled, cable with an open headphone? This cable would make more sense for a portable closed pair. The HE-400i uses the same coaxial cable connectors as the previous generation. Personally, I’ve never had an issue with this technology but I know many despise it.

The headphones themselves are primarily made of a light plastic with some metal here and there. They simply look amazing. Beside the HE-400, they don’t look as heavy-duty or strong. But once they are handled, it becomes apparent that the construction is solid. The main chassis is made out of metal. The headband seems to be made of layered fabrics with faux leather on the outside. No issues with the stitching. The gimbal portions are a matte black plastic, in comparison to the HE-400’s metal. The cups are a shiny silver which reflects different colour tones based on the lighting. Very aesthetically pleasing, but I wouldn’t put too much faith into them staying pristine. The outer shell or paint seems weak. My unit has some scuffs and imperfections on the cups. When I asked Hifiman, they told me that my unit wasn’t “new” implying that it was pre-handled. My HE-400, on the other hand, doesn’t have that issue with the cups. The grills of the two headphones are the same.

Pads included with the HE-400i are the new FocusPads. They are loosely based on Jerg’s modified pads. Angled pads with pleather on the outside circumference and velour at the end. They look and feel better to the touch than the pleather and velour pads of the old generation headphones.

Comfort
The new headband system is a very welcome change to me. Although thin and not well padded, the headband is very comfortable as it is wide and flexible, adjusting naturally to the shape of your head. The overall weight of the HE-400i is much less than the HE-400. When worn, it feels even lighter, due to the weight distribution of the new headband. In comparison, the HE-400 headband is much more inflexible, smaller, and uncomfortable. Another issue with the HE-400 was that it wasn’t friendly with smaller heads. The clamp was not enough, and even at the smallest setting – it was too big. The HE-400i adjusts wonderfully to a large variation of head sizes. However, Hifiman overcompensated when trying to remedy the clamp issue. The clamp is now ridiculously strong. I have never felt a clamp like this in a headphone before. Pulling the cups away from each other feels like you’re prying two magnets from each other (and in a way, you are). But when actually wearing the headphones, I didn’t have an issue with the clamp. Then again I have a small-average head, and I foresee many with larger heads having issues. The FocusPads are a step up for the most part. First, the pads themselves are very spongy and feel great around your head. The fabric used for the velour portion is also very nice on the skin. Much better than the HE-400 velour material. The pads are however shallower so it is more likely that your ear will touch the drivers. The inside diameter is also smaller so your ears will be touching more of the pad. For reference, my ears slightly touch the drivers on the HE-400i and the edges of my ears touch the inside pads. But with the HE-400 with velour pads on, my ears hardly touch anything. Which is more comfortable will be up to the user. All in all, the changes in comfort are a huge improvement. Within a few minutes, it always feels like the HE-400i has disappeared on my head. I don’t think anybody has ever said that about the HE-400.

Sound
The HE-400i is a 35ohm headphone with a 93db sensitivity. Almost the same as the HE-400 and should be fairly easy to drive. I used an Objective2 amp with the Fiio E17 as my DAC. The sound signature of the HE-400i is very balanced. If I heard this headphone willy-nilly, I would’ve never have guessed that it was the predecessor of the HE-400. It sounds closer to the HE-500, but even that comparison isn’t perfect. It’s certainly not v-shaped like the HE-400. I can’t pick out which frequencies are elevated above the others. It just sounds very neutral without being boring. Going to the HE-400 from the HE-400i, I can feel sounds missing from the music. Tonality is probably what the HE-400i does best. Everything sounds so accurate and natural. Similar to the HD600, maybe a smudge warmer if anything. None of that weird timbre that the HE-400 suffers from. Speed is also very good, on par with the HE-400. As is the detailing and clarity.
 

1. Treble

Treble is great. Well extended. It doesn’t have any of the imbalances that the HE-400 treble faced. I never noticed any stridence or sibilance. The HE-400 on the other hand is known to be sibilant with certain recordings. The HE-400i’s treble has a harder texture to it, and some may not like it over the soft airy treble of the HE-400. Part of this may have to do with the fact that upper treble is emphasized over the lower treble on the HE-400.
 

1. Mids

The mids will be the biggest shock to anybody coming from the HE-400. They are no longer recessed at all. I would go as far as saying the mids are forward. Tonally, they aren’t too thick or too thin. Both male and female vocals sound impeccable. Due to the forward mids, vocal presentation is up-close and personal. It sounds like the singer is right next to your ear. Some may like this, others may not. In comparison, the HE-400’s vocals sound much more distant due to the recessed upper midrange and lower treble.
 

1. Bass

Initially, the bass is what disappointed me the most and I am still disappointed. The bass is very nicely textured and accurate for the most part. However, it lacks the impact, body, and quantity that the original HE-400 had. Subbass, although not terrible, also doesn’t extend as well as the HE-400. Some may love the accuracy and neutrality of the bass, others will find it thin and boring. One of the main thing the HE-400 had going for it was the bass. It extended very low, was linear, and was powerfully pleasing. It was unparalleled in its price class. The only headphone I’ve heard which I thought did bass better was the Audeze LCD-2 at three times the current HE-400 cost. Not sure why Hifiman would go this route with the low end, especially when they released another can, the HE-560, which is supposed to be more of a reference product. Regardless, the bass isn’t terrible but if the bass was the main reason you liked the HE-400 then purchasing the HE-400i will be a downgrade in that regard.
 

1. Soundstage & Imaging

The biggest weakness of the HE-400i is the soundstage. The headphone simply does not sound very open at all. The soundstage is small and has an in-your-head sound. Very reminiscent of the LCD-2 – but more closed it. Some may prefer the intimate, close to the ear, sound, but others will find it congested and suffocating. There is OK depth, but very little width. The HE-400 by comparison has a much bigger soundstage, it is a very open sounding headphone. Fairly wide and deep. AB-ing between the two headphones, the “openness” is the most obvious advantage you’ll hear from the HE-400. There are two things which I think are contributing to the closed soundstage of the HE-400i over the original. The first is the signature. The forward mids and overall balanced signature sounds a lot less spacious than the v-shaped signature. Secondly, the shallower FocusPads (compared to the stock velours) may be to blame for the in-your-head sound since your ears are closer to the driver. Considering the limitation in soundstage size, I think the HE-400i pulls off imaging decently. Sounds come from where they should be coming from, but compared to the HE-400, the HE-400i does not impress. The HE-400 imaging is interesting, you can hear sounds popping up from empty spaces of air all around your head. Many are a fan of this, but others will criticize it for sounding weird and praise the HE-400i for sounding more natural and coherent. Instrument separation is good as well but due to the limitation of soundstage, sound signature, and lack of air in the treble – it doesn’t sound as great as the HE-400. Frankly, the HE-400i sounds pretty compressed and not very dynamic.

Value
At $400, and later $300, the HE-400 was a great buy and has always punched above its weight. The HE-400i, at $500, can hold its own against competitors like the Sennheiser HD600, HD650, Oppo PA2, Mr. Speakers Alpha Dogs, Beyerdynamic T90, DT880, and Hifiman’s own HE-500, but it’s clearly not the obvious choice in terms of value. Consumers are more likely to purchase something with better reputation and popularity over a new product – especially if it’s priced the same. The inevitable future price-drop is what I think will drive its popularity.

Conclusion
Overall, the new HE-400i does so much right and so little wrong. It is a great all-rounder open headphone and will definitely please many audiophiles. It’s a very technically proficient headphone. What it isn’t though, is a true replacement for the HE-400. Instead of just refining the HE-400, Hifiman took all the weaknesses and overcompensated for them – and in turn killed all the attributes the HE-400 was known for. Fit kind of loose? Let’s make it clamp like crazy. Pads are too hard? Let’s give them the squishiest pads ever so your ears practically touch the driver. Upper mids and lower treble a little unbalanced? Let’s get rid of the upper treble airiness and push the mids all the way to the forefront. Now we’re left with a headphone with a small soundstage, underwhelming bass, without the airy treble, overall spacious sound, or fun v-shaped sound signature. It’s a great headphone, and I may keep my pair, but it won’t be replacing my HE-400, even if it is “better”.

TL;DR: The HE-400i is a very comfortable, very balanced, easy-to-drive, Hifiman can with OK bass and a small soundstage. Not a true sequel to the HE-400.

Note: this is my first attempt at a proper headphone review and I’d love some feedback.

 These IEMs have an MRSP of $40. For that price they are not worth it. However, in many discount places, especially in Canada, you may find these @ $15 or less. If you find them for this price, grab them. I personally paid $10. 

Sound is great for the price. They look very rugged and feel solid, I believe they are made from aluminum. The cord is also tangle free and feels very nice. Despite this they aren't the most hardy, they started falling apart and then stopped working a few months into use. And I was not harsh with them. The comfort is average, isolation is great. They include a small carrying case.

Overall, they're great budget IEMs for using in the gym or while being active. Just don't expect em to last forever.