[giveway]

Pulled the trigger on these.

I was worried about the small cups, but they fit my ears perfectly. They also may be very shallow, but even if my ears are touching the drivers, I certainly can't tell. Overall, no complaints whatsoever comfort-wise.

And now to the tricky part:
Out of the box, they were almost unlistenable. Thin sound and a very, very harsh treble. Which was a huge surprise, given the fact that most people have been talking about bloated bass and muddy sound before burning in. Mine sounded exactly the opposite! I did not panic though and was willing to make up all sorts of excuses: new headphones, my ears are not adjusted to them, they need burning in etc.

After about 40 hours of burning in (combination of pink, white and brown noise), I noticed a slightly more present bass, while the treble has softened a bit, but it's still quite harsh at times and definitely has an artificial timbre. Sibilance varies from non-existent to very present; another quite puzzling aspect. The details are there and all, but overall these hp make for a pretty uninvolving and, after a while, fatiguing and unpleasant listen.

I'm not a bass head or anything, but I prefer a warm and full bodied sound, which was exactly how people have been describing the AH-MM400. So far, it's anything but that. I'm willing to reach the 100 or 150 hour mark of burning in, but I doubt they will change that drastically and get a completely different sound signature.

ps) my setup: MacBook Pro--> iFI iDSD Micro-->AH-MM400, using flac files downloaded from hdtracks played in Audirvana+.

 

[Bark Snarly]

Weird, none of those things are how I would describe the mm400 at all, it's most definitely a warmer, thicker sounding headphone... Are you sure the cable is plugged in all the way? It requires a pretty hard push to get it solidly locked into the headphone end on my pair.
 
What headphones are you coming from too if you don't mind me asking?

 

[Kdraper]

Does anyone know where I can find a longer cable for the MM400?  I'm using them in my office but the cord is too short to reach my amp and I can't seem to find any cables that fit due to the narrow opening for the cable.

 

[giveway]

I know, most people have been describing them like that, which was one of the reasons I bought them.
Strange that you should mention the cable, because it was already in place when I opened the box (which was sealed by the way).

This is my first full size hp, I'm more of a speaker guy. I have owned a bunch of iem's though, including Denon CX700 and Sennheiser IE8. I was very happy with the latter especially.

 

[BobMonkhouse]

I'm sorry to read about your experience with the MM400 so far. Mine never sounded thin nor sibilant even at the beginning. And I'm very highs sensitive, especially at 7 kHz. The only thing I can guess is a bad synergy with your amp. I've ready the iFi quite analytical. I don't like the sound with my Fiio E12A which has too much treble for me and a bit recessed mids. It's just prefect with my Cayin C5.

 

[provision]

Regarding burn-in for these, mine sounded great out of the box (mint, unopened, new wooden smell) and I can’t say I hear any difference a couple of hundred hours later. Maybe it’s me not knowing what to listen for or maybe it varies from pair to pair.

 

[Romani]

Even out of the box, these never sounded thin or sibilant. Even now that the bass has settled, and the mid range and top end have more presence, they are not even mildly ear piercing or artificial. Almost sounds like you're describing a completely different set of headphones to be honest. I agree with the bad synergy comment. Try a different source, even a PC and see if your impressions are the same.

 

[Romani]

Does anyone know where I can find a longer cable for the MM400?  I'm using them in my office but the cord is too short to reach my amp and I can't seem to find any cables that fit due to the narrow opening for the cable.

Please see a few pages back. There is a cable that comes in different lengths that fits the cans perfectly which I stumbled across on ebay.

 

[subguy812]

@giveaway...I know this sounds dumb, but make sure the cable is in as far as it can go.

 

[Kdraper]

Please see a few pages back. There is a cable that comes in different lengths that fits the cans perfectly which I stumbled across on ebay.

 
Thanks, I just ordered one.  I hope it fits.

 

[Zaroff]

Even out of the box, these never sounded thin or sibilant. Even now that the bass has settled, and the mid range and top end have more presence, they are not even mildly ear piercing or artificial. 

 
This. I never got one sibilant syllable since I got them. They sound exquisite, deep, and never harsh nor aggressive.

 

[Romani]

Thanks, I just ordered one.  I hope it fits.

I have one and I can confirm it does.

 

[148124]

I don't want to ruin original 2 cables from denon so I am going to buy this cable and reterminate its ending to 4 pin neutrik XLR and make balanced cable trying m400 with some amazing amps in balanced mode ... audio-gd nfb-28, nfb-6, nfb-27, bryston bha-1 etc
 
Only need to make sure whether there are separated grounds from each channel in this cable (4 wires, not 3 and 4 pins connector that goes inside phones)
 
Let you know how m400 reacts and scales with nice amps. Also for the best results dac has to be fast, detailed and neutral as much as possible - there is amazing synergy then
 
EDIT: oh just have seen the picture of connector that goes to the headphones - that sucks, only 3 pins, so it shorts separated grounds from both channels at the beginning ; / so I can only sacrifice original cable to make it balanced one

 

[Romani]

I don't want to ruin original 2 cables from denon so I am going to buy this cable and reterminate its ending to 4 pin neutrik XLR and make balanced cable trying m400 with some amazing amps in balanced mode ... audio-gd nfb-28, nfb-6, nfb-27, bryston bha-1 etc

Only need to make sure whether there are separated grounds from each channel in this cable (4 wires, not 3 and 4 pins connector that goes inside phones)

Let you know how m400 reacts and scales with nice amps. Also for the best results dac has to be fast, detailed and neutral as much as possible - there is amazing synergy then

EDIT: oh just have seen the picture of connector that goes to the headphones - that sucks, only 3 pins, so it shorts separated grounds from both channels at the beginning ; / so I can only sacrifice original cable to make it balanced one

I don't know what impact the pins on the connectors have but I can tell you the sound is similar if not identical to the original cable.

 

[bluesaint]

Honestly I don't know how much a balanced cable will help at all given the cans don't have individual connectors for each side.  The cable connecting left side to right side is internally routed within the headband.  my 2 cents.