Just finished up at the Chicago meet, and I have to say the HE-400i was one of my two favorites of the show! I am always most impressed by manufacturers that can do a lot inside a reasonable price. I enjoyed the 560's but for $1K there is a LOT of competition. I think the 560 is still competitive, but the 400i is my realistic end game open can. On to the impressions (I spent a TON of time at the HiFiMan table and they happened to have music in very familiar with)
My first impression of the can was: "dam, these are comfy!" I own Grados so typically comfort is a whatever factor for me. If a phone has above average comfort it's nice but I usually don't pay it much mind, but these were the most comfortable phones of the entire show, from on-ears all the way up to the STAX-009. Most comfortable headphones I've experienced. They're light too, but they feel well-made, they're really a beautiful headphone in person! I will note that I felt there was plenty of space and adjustability. I have a big fat head and small ears by western standards though, so take that with a grain of salt. I think they'll fit a fair variety of sizes though.
I'll preface the sound section with a few quick comments: I am a musician, I've played shows, attended tons of live concerts both classical, jazz, rock, pop, etc. and listen to both speakers and headphones of all kinds, but I started on loudspeakers.
Alright, onto the important part - Sound!
They are thicker sounding than the 560's. They were still very clear though, but they had just a slight tilt towards wariness, but I still found plenty of detail available for listening critically. Even though the sound was a little thicker the detail was on par with the perceived detail of the Audeze LCD's there, just by nature of the audeze warmness. The 400i was airier though, more open, a lighter sound. I personally find really bloated or excessive bass tuning to be extraordinarily fatiguing. Bass heavy closed cans and the like make me a bit nauseous. These cans had clean, present bass, and more of it than the 560's when driven out of the HifiMan amps, but I felt that the lighter, airier nature of the sound made it sound superb and plentiful without being fatiguing. This brings me to my main impression of these cans; they are precise, reasonable cans. By reasonable I mean moderate - the weight feels great, the sound is gorgeous but neither overdone nor under-supported. Some listeners may find them quite light because of the glut of over-warm headphones on the market. These seem to take a step back from the intimate dark presentations that were the order of the day with many popular orthos present at the meet and popular today. They seem a lovely middle ground between too light and too dark. They are just right, for me at least. The tilt of the sound towards a little thicker I found more to my tastes than the 560. I heard the 560 off an Audio-gd at the meet, and the bass was much more on par with the 400i but I feel that the 400i is less fatiguing. I didn't feel any fatigue at all from the 400i, but I felt that long periods with the 560 would be just slightly fatiguing. The 560 too, while very good, was not as engaging with low amounts of power as the 400i. I tried the 400i out of my phone (something I never really listen out of, but I tried just to see) and it still sounded great. The 560 was just boring out of a phone.
The highs were the sweetest, clearest non-sibilant highs I heard at the show, with the possible exception of the 560. I was rather alarmed by the amount of sibilance I heard in high-end cans there, and many cans that didn't have them lacked high end response, which is really not something I personally would want if I were looking for a balanced, high-end headphone. I listen at low levels too, at most I'll listen at low-medium/medium. I'll turn some cans up a bit when at meets or auditioning, but I try to retain my hearing (and it encourages critical listening) $600 for sibilant highs, though? No way. (I'm looking at you Alpha Dogs)
No sibilant highs, but much more punch and shimmer up in the highs than the Audeze's there. The punchier dynamic triangle and cymbal hits seemed just as good as cans that had good but sibilant highs, but I never felt sibilance. Again, I think the very open sound, and lighter weight of the sound (compared to a lot of the popular, very dark orthos) helped with that.
Mids were gorgeous. In a classical and jazz trains singer who does a lot of genres, as well as playing piano and French horn. That's pretty much all mid focused. I heard cans there that were almost a quarter time sharp (meaning it was playing higher than the original note to make it sound sweeter) but this was not the case. Pitch has a lot to do with how natural something sounds, and these were spot on. The 560 sounded perhaps more precise, but pitched maybe a little flatter than the 400i's. Both sounded more natural than almost anything there in my opinion (again, I'm more experienced with real instruments and loudspeakers than headphones, so take that with a grain of salt)
In conclusion, the sound was not "lovely" perhaps a tad "lush" or "thick" but most of all it was just "right." I felt it had a nimbleness too it without sounding thin. The bass was perhaps a little more than neutral but not much. I would personally be comfortable using these in the studio. In fact, I would choose these over a good number of other cans. And for a can that you can use for both critical and relaxed listening these are great. My realistic end game would be these and a solid state amp like magni/modi combo.
I will say that with the caveat that they leak more sound than any of the headphones I heard there. They also let more sound in, but I don't see this as a negative.
I say well done HiFiMan, I'm going to sell my Grados and pick these up as fast as I can pinch my pennies.
