[llcook51]

  Can anyone compare 400i to AKG k712 ?

I have both. I like the k712. It is a substantial improvement over the k702.
I think the 400i has a smoother and "richer" sound. The AKG sound is un-colored and very precise. 
Both are very comfortable to wear.
For long-term listening, I think the 400i  is more enjoyable. It is more forgiving on moderately recorded music.

 

[skyline315]

  Any thoughts on burn in time? Its my second new HP, I didn't notice anything in the first one. Wasn't really paying attention though.
 
Did take a quick listen after 30 minutes, was a bit diffused sounding.

HiFiMan recommends 150 hours.
 
Seems a bit excessive to me, but who knows.
 
I did notice a difference after the first 75 hours or so.  The sound became a little smoother and more coherent and some of the initial harshness that I heard seemed to have mellowed out.
 
Whether there was a real change or whether it was all in my head, I couldn't say.  

 

[Mike In Bama]

A 150 hour break-in sounds pretty reasonable to me. My home speakers (Maggie 1.6), also planar, took about that long to 99% of where they eventually wound up. That last 1% took a couple of extra weeks.

I don't consider myself particularly crazy, but I'll take to my grave that I heard the sound gradually improve. Eventually the improvement stopped. I don't think it was my brain adjusting to the sound as I was then able to hear the same shortcomings I heard in the showroom.

 

[Ekul61]

I have a new pair delivered today.. if they dont blow my he400 away. Im sending them back... it will be hard to burn them in.. In the 30 day grace period. 150hrs is a lot in 30 days... hopfully in a week I will know if im keeping them.

 

[money4me247]

A 150 hour break-in sounds pretty reasonable to me. My home speakers (Maggie 1.6), also planar, took about that long to 99% of where they eventually wound up. That last 1% took a couple of extra weeks.

I don't consider myself particularly crazy, but I'll take to my grave that I heard the sound gradually improve. Eventually the improvement stopped. I don't think it was my brain adjusting to the sound as I was then able to hear the same shortcomings I heard in the showroom.

...wouldn't the showroom speakers probably have a ton of hours logged in on them as they are constantly being demoed?
 
Final food for thought, what is the actual mechanism for the changes in sound quality and why is it that it always positively affects the sound?

 

[Mike In Bama]

Absolutely the demo speakers are well broken in. Thankfully, you should have the opportunity at it's absolute best.

What are the mechanisms at work? I have no idea. Maybe a molecular scientist could explain it.

That is an interesting question wondering why the sound always improves. The only thing coming to mind is that during R&D, they make notes on their manufacturing technique. Do they burn-in their gear before testing and listening? I would assume so.

Assuming can get you in trouble in a big hurry fast, I realize. But would it not be reasonable that they assemble and ship products that are not burned-in? Considering time constraints that makes pretty good sense as well.

Is it that different from buying a new car? Right off the bat you are warned to drive at different speeds the first 500 miles? Ford knows what kind of torque and HP you will wind up with, eventually. They just don't promise that right off of the lot.

 

[Gateway]

  I have both. I like the k712. It is a substantial improvement over the k702.
I think the 400i has a smoother and "richer" sound. The AKG sound is un-colored and very precise. 
Both are very comfortable to wear.
For long-term listening, I think the 400i  is more enjoyable. It is more forgiving on moderately recorded music.

Thank you, as im producing music on headphones (yes, speakers are out of question at the moment) i know that i should probably go with k712

 

[money4me247]

lol. I personally think that since burn-in almost universally makes headphones sound better, it is probably more likely some sort of psychological phenomena. Also, the current studies done on burn-in for headphones have not concluded that any significant measurable changes in sonic performance. The subject of burn-in thought gets pretty crazy, so I'll just leave it at that.

 

[Billheiser]

I've heard that the tight suspension (the surround) of a speaker cone or headphone dynamic driver gets usefully loosened up with burn in. But if it does, seems like it would keep on loosening up over time, instead of stopping at some magical point and then being optimal from that point on.

 

[mandrake50]

http://www.audioholics.com/loudspeaker-design/speaker-break-in-fact-or-fiction

http://www.innerfidelity.com/content/measurement-and-audibility-headphone-break

I can only speak for my own personal experience. I have never heard this break in change.

I spent around 15 years working with an outfit that built thousands of speakers for Sound reinforcement and later home stereo use.
Not saying it doesn't happen, just that I have lots of experience, and was trained in analytic listening, and it is outside of my experience.

 

[wrists]

hi, i bought the he400i recently. i really like them but the cable is very short
 
my question: if i buy an extension cable, will that make the sound quality worse or something in any way?
 
like this one for example: http://www.thomann.de/gb/cordial_klinke_maleklinke_female_3m.htm

 

[MattTCG]

The extension should be fine. Just don't add more than about 4-5 feet. They say that balanced allows for longer runs of cable. Or you could just make or order a custom cable. 

 

[MrMateoHead]

A 150 hour break-in sounds pretty reasonable to me. My home speakers (Maggie 1.6), also planar, took about that long to 99% of where they eventually wound up. That last 1% took a couple of extra weeks.

I don't consider myself particularly crazy, but I'll take to my grave that I heard the sound gradually improve. Eventually the improvement stopped. I don't think it was my brain adjusting to the sound as I was then able to hear the same shortcomings I heard in the showroom.

What do you like and hate about the Maggies? Just wondering - as I would be interested in getting them sometime for a 2.1 setup.

 

[Ekul61]

First hr of listening. Quite clean sounding. Base is just fine... its only been a hr... so far not as fun sounding as the basic 400. I will report back soon. X5 , e12 diy

 

[swspiers]

  ...wouldn't the showroom speakers probably have a ton of hours logged in on them as they are constantly being demoed?
 
Final food for thought, what is the actual mechanism for the changes in sound quality and why is it that it always positively affects the sound?

LOL!
 
You just like stirring things up (but in a pretty cool way)