"Burning in" headphones is a practice wherein a user plays audio through their brand new headphones for a number of hours or days at a stretch in order to break them in and bring about the best sound from the headphones.
If you talk to 10 audiophiles in a room, it's likely that each person would have a certain magic number of hours that they've burned in their own headphones for. This number is usually as short as 4 to a ridiculous 400 hours!
How to burn in headphones?
Burning-in or breaking in new headphones is a practice of playing audio through them with the belief that like any mechanical product it needs to be used a fair amount before realizing its full potential.
How many hours should you burn-in headphones?
Believe it or not, there is no prescribed science as to how long one needs to burn in new headphones. Some people advise 100 hours while some audiophiles aren't happy till they've touched the 500 hour mark.
How does burn in change the way my headphone speakers sound / drivers act?It is claimed that burning in headphones with a specific type of audio is bound to have some affect on the sound. The truth is, if a headphone is incapable of a certain kind of sound, there is nothing one can do about it.
Is there a way to prove that burn-ins make a difference?
There isn't, actually. There are way too many variables. One can conduct experiments out of curiosity or for fun but the results are never conclusive: could it simply be just movement?; if it were tested on another brand new pair would you get the same results?; or if you tried it on an already broken in pair would you get the same results? Nobody knows for sure.
Steve Guttenberg of CNET says "I believe headphones' sound "matures" over time, and I recently had the chance to compare a brand-new set of Etymotic ER-4PT in-ear headphones with my 10-year-old ER-4Ps. I felt the older set was "slightly more 'relaxed' and more laid-back in its tonal balance." The two models have identical specifications, and yet they sounded different."
The guys from WIRED completely rubbish the idea of burning in new headphones: "The ambiguity and voodoo can confuse buyers and quickly turn into a colossal waste of time. The fact is burn-in has now become tribal knowledge. You might as well be kissing each earpiece 50 times to see what sonic difference that makes."
Interestingly, top audio expert Tyll Hertsens from Inner Fidelity ran tests on a bunch of AKGs and concluded, "it's clear to me, having had the experience, that there is indeed an audible difference when breaking-in a pair of Q701 headphones. I've seen measured differences, and now experienced audible differences. While the measured differences are small, I believe the human perceptual system is exquisite and able to perceive, sometimes consciously and sometimes sub-consciously, subtle differences. The differences I heard, while evidently fairly obvious to me, were not large. I'm absolutely convinced that, while break-in effects do exist, most people's expressions of headphones "changing dramatically" as a result is mostly their head adjusting and getting used to the sound."
Because there exists no clear industry standard, and there is no quantifiable evidence debunking the advantages of burning in new headphones, audiophiles everywhere usually have to run their own tests or follow blindly the select few brands' prescription for a burn-in.
But guess what: it costs nothing, it does no damage to the headphones, and you could lose more not believing in the idea of a burn-in or break-in than otherwise.
However, don't conform to burn-in guides where you've been given step by step instructions of listening to a particular album, or a particular type of file. Definitely don't blast your new headphones with pink or white noise. Some websites go as far as to say that headphones sound "weak" when it's first taken out of the box, and that it should be burned-in with regular breaks, and not in a marathon session. Ultimately, we feel that these kind of extremist burn-in practices could possibly not make an audible difference.
If you have to burn-in your headphones, the objective should be to get comfortable with the sound. This is easily achieved with simply listening to the headphones for a few hours. Post playback, considering you invested in good headphones in the first place, it should be apparent that the sound is better simply because you've dedicated a good amount of time in just getting to know them.
To put it simply, you should take the practice of a burn-in with a pinch of salt. There is no mandatory burn-in required for new headphones, neither is the difference in sound significant because of burning in.
That said, it is important that when you buy new headphones, you should spend a decent period of time listening to different kinds of music. Besides burn in, you certainly shouldn't ignore basic comfort. Getting the right fit is almost always the key to bringing out optimal sound. With circumaural headphones, it is essential that you have comfortable contouring earcups, and with earphones you should consider memory foam or double flange tips.
Whatever you do though, if it's with the pursuit of achieving the best possible sound, it's probably worth reconsidering your entire setup. Starting with the audio file, or the amp being used to run the headphone, or finally, the audio player.