[Beagle]

I had just posted in the 555 thread regarding it's improvement after burn in. Seems that it starts out bright and bass-shy, then becomes better with run-in.
 
It seems that (after burn-in) a 'phone that starts off bright and bass-shy always gets less bright and more bassy. And one that it initally dull and bass-heavy goes the opposite way, to end up with a desireable balance.
 
Is it possible for a headphone that starts out bright and bass-shy to become even more bright and bass-shy (or for one to become more dull and bass-heavy after 100 hours of burn in? If it is not possible, why?

 

[bdr529]

You have stumbled upon one of the great mysteries of headfi. Somehow burn-in can only make things better; Bass-light headphones get more bass, bass heavy headphones get more controlled.

 

[zmd]

Yep. Burn-in is the great equalizer that makes all headphones sound good (if you really really want it to..)

I've started to doubt it even exists as I've learned to appreciate my headphones for being different, but still sounding good.

 

[Beagle]

Quote:

Somehow burn-in can only make things better; Bass-light headphones get more bass, bass heavy headphones get more controlled.

....and everyone gets acclimated to their headphones.
 

 

[kingtz]

I've definitely noticed changes in sound after "burn in", but how much of that I can attribute to either actual burn in or acclimation is anyone's guess. And if burn in does actually occur by way of loosening of the diaphragm or settling of the drivers, then my guess is that it'd probably occur a lot sooner than the standard 100 hours that most of us here have burned in our headphones for.

 

[LowPhreak]

Burn-in is not a phenomena just with headphones, but is often the case with speakers and electronic components as well. 

 

[nikongod]

 
Quote:

You have stumbled upon one of the great mysteries of headfi. Somehow burn-in can only make things better; Bass-light headphones get more bass, bass heavy headphones get more controlled.

My ultrasone HFI-780 went from bass shy to about right to laughably tasteless (and uncontrolled) as they burnt in.
 
Depending what you want from the headphones, they may get worse. I think its safe to say that they sound how the designer intended after a few good hours of play though. 

 

[Albedo]

My Sennheiser MX 880 became less shrill, more responsive and the lifeless bass went down were it belongs. That was after about 70 hours of white noise burn in overnight and about 10 hours of music listening. After that I stopped listening to the sound and started enjoying the music.
 
.. but opinions differs: http://www.matrixhifi.com/ENG_contenedor_rodajealtavoces.htm

 

[Beagle]

Quote:

Depending what you want from the headphones, they may get worse.

 
Until the perfect headphone comes around (which will never happen, unless all listeners suddenly become perfect themselves) we will simultaneously lose and gain with each headphone sound.
 
I didn't want this to become another generic burn-in thread. I was just curious about burn-in having a negative effect on headphone sound. Why does burn-in always "correct" supposed initial out-of-the-box "problems"? Shouldn't they be at their best right away, when everything is nice and tight, so you get a nice fast, tight sound? And if one only listens at low volumes (personal preference), do they ever feel the effect of burn-in? Will the diaphragm eventually accumulate a layer or film of oil (from use) which would have a damping effect?
 

 

[Albedo]

Rubber or iron (piston and cylinder), it's the same principle of repetition before settling in a known pattern of least resistance.

 

[matthewh133]

From memory, when I first got my AD900s they sounded very bright and even sometimes harsh. Now it seems they are still bright (which I like), but the harshness is all gone, and the bass is tighter.

 

[nikongod]

Quote:

I didn't want this to become another generic burn-in thread. I was just curious about burn-in having a negative effect on headphone sound. Why does burn-in always "correct" supposed initial out-of-the-box "problems"? Shouldn't they be at their best right away, when everything is nice and tight, so you get a nice fast, tight sound? And if one only listens at low volumes (personal preference), do they ever feel the effect of burn-in? Will the diaphragm eventually accumulate a layer or film of oil (from use) which would have a damping effect?
 

Too late. burn in FTW.
 
In hte most general sense: Why do headphones sound better burnt in than fresh from the box?
 
The answer is simple. The guy (or girl) who was tuning the damping, ports, screens, and the like in the headphones didnt take a new driver out of stock every time he put another piece of felt or aperiodic membrane in the headphones. He used the same drivers he was given on day 1 for several weeks of tweaking about.
 
In the case of people who "dope" drivers, how often do they start with a truly un-used driver? quarter to never... 
 
With fairly naked headphones where the drivers are what is (are?) unique a few sets of different prototype drivers are built and passed around for a few months. A general agreement is reached, but by that time the drivers have several months of use on them.
 
In speakervile we again see how burn in can have an effect. If the crossover designer was competent he no doubt tried several designs, over the course of several days. His good friends came over and had a party then they compared notes... and so on and so forth. 
 
NOBODY puts a product to market that they didnt like the sound of burnt-in. 

 

[kingtz]

Quote:

Why does burn-in always "correct" supposed initial out-of-the-box "problems"? Shouldn't they be at their best right away, when everything is nice and tight, so you get a nice fast, tight sound?
 

 
I think that's kind of the opposite reasoning to how burn in works. Rather that being best right away, the diaphragm and other moving parts are supposedly stiff from being so new and unused. Headphones only start sounding their best once things loosen up. Perhaps burn in only ever improves the sound because maybe headphones cannot sound worse than being all tight, so any change will seem an improvement - until you take it to the other end of the spectrum when all the moving parts are so loose and worn out that it starts sounding crappy again. This is all just speculation, of course.
 

 

[nessinonett]

I always assumed the diaphragm is stiff out of the box and needs time to loosen up. More range of motion = more air moving through the headphones.

 

[Albedo]

Quote:

That was after about 70 hours of white noise burn in overnight and about 10 hours of music listening. After that I stopped listening to the sound and started enjoying the music.

 
I have to correct myself after this weekend when the buds laid unused for several days, when I yesterday tried to discern the basslines of the song Choirs of Spirits by Obscura I had great difficulty at that on some passages. I then burned the buds overnight with a high frequency sweep 0 -> 30 kHz and now the lines are as clear as before the weekend. My perception yesterday was of an very annoyed character and my emphazises could be what OP points to after burn in, if I didn't know any better I would have sold the buds and not opted to burn them in another additional 80 hours.