[Pro-Jules]

It was a lucky break back in 1981 or 2

 

[castleofargh]

No proof, but it's interessting that focal has a page on their website about burning in their loudspeakers. The cause being that the mount is rigid and needs to adapt to temperature and humidity.
https://www.focal.com/en/focal-teach/what-is-the-running-in-period
I know it's not headphone drivers, and that there's no measurements, but it's coming from a big company.
When i bought an Audioquest Nightowl, they also said in the manual, that you shouldn't trust the sound having settled until it reached 150 hours of burn in.

Another question.
The difference might not be in frequency response, but in soundstage and the details. If that's so, how can you measure that?
I'm not really a smart guy so don't roast me

Some types of changes have been demonstrated on rather large speakers. The audibility of it is another matter(maybe just because it's impractical to set up a listening test, as you need the same device at different moments in time, so nobody bothered?). But at least we have public data shared on those objective changes affecting the sound. Headphones, while using similar dynamic driver tech, are also different in many ways(size, shape, material, impedance, mostly no surround involved, ...). So just pushing what we know of speakers onto headphones and concluding that it's the same, is a really bad idea IMO. Almost as bad as letting memories of sighted impressions be the judge of objective changes.

Manufacturers telling you to burn in gears for XXX hours is the easiest trick in the book to stop someone ready to send something back, make him have second thoughts and keep the gear until he either gets more used to it, or passes the return policy limit. I don't mean to say that all manufacturers of all products in the world talking about burn in are doing it for that reason, but I'd bet that several do. Because it costs them nothing, and might easily save them money. In the world of marketing that seems like a no-brainer.

Soundstage is an impression. Like any other, it is born of interpreting and mixing up various information(not necessarily limited to hearing). So we have to pick what we wish to test for. If you're only curious about possible "soundstage" impact from the sound itself, then we need to set up a test where people don't know what they're listening at. So that only sound can have an impact on the result.
What can change the subjective impression of "soundstage"(in a very large improper sense), is most of the audible sound. So the obvious solution to factually measure a change, would simply be to record signals and music before and after "burn in" periods, then check for differences. That can easily settle the question of objective change in the sound over time.
What it does not settle is knowing if that change is caused by "burn in"(whatever that really is supposed to mean, as we've already seen anecdotes about guitars...). I've measured significant change over time at magnitudes easily audible with my own headphones, but so far the most obvious contribution to sound change have always clearly been the pads and how they change over time. Because anytime I've tried to record or measure stuff without pads, the differences I so easily found before were gone. Instead I got changes so small that I cannot tell you if it's ambient noise, measurement artifacts, or actual change from the driver's sound.

 

[old tech]

No proof, but it's interessting that focal has a page on their website about burning in their loudspeakers. The cause being that the mount is rigid and needs to adapt to temperature and humidity.
https://www.focal.com/en/focal-teach/what-is-the-running-in-period
I know it's not headphone drivers, and that there's no measurements, but it's coming from a big company.
When i bought an Audioquest Nightowl, they also said in the manual, that you shouldn't trust the sound having settled until it reached 150 hours of burn in

The manual that came with my speakers specifically says burn in is not required. The way it is stated implies burn in is a audiophiles/marketing myth.

 

[bigshot]

I'd imagine that if there is a change in large woofers, it would probably happen in the first few seconds of being brought up to volume... sort of like popping into gear after being bounced around in shipping. It seems to me that gradual long-term changes would be more apt to be degradation than it would be improvement.

 

[Glmoneydawg]

The manual that came with my speakers specifically says burn in is not required. The way it is stated implies burn in is a audiophiles/marketing myth.

Yep...Allan Shaw of Harbeth says break in is a crock.

 

[Goldvein]

Some types of changes have been demonstrated on rather large speakers. The audibility of it is another matter(maybe just because it's impractical to set up a listening test, as you need the same device at different moments in time, so nobody bothered?). But at least we have public data shared on those objective changes affecting the sound. Headphones, while using similar dynamic driver tech, are also different in many ways(size, shape, material, impedance, mostly no surround involved, ...). So just pushing what we know of speakers onto headphones and concluding that it's the same, is a really bad idea IMO. Almost as bad as letting memories of sighted impressions be the judge of objective changes.

Manufacturers telling you to burn in gears for XXX hours is the easiest trick in the book to stop someone ready to send something back, make him have second thoughts and keep the gear until he either gets more used to it, or passes the return policy limit. I don't mean to say that all manufacturers of all products in the world talking about burn in are doing it for that reason, but I'd bet that several do. Because it costs them nothing, and might easily save them money. In the world of marketing that seems like a no-brainer.

Soundstage is an impression. Like any other, it is born of interpreting and mixing up various information(not necessarily limited to hearing). So we have to pick what we wish to test for. If you're only curious about possible "soundstage" impact from the sound itself, then we need to set up a test where people don't know what they're listening at. So that only sound can have an impact on the result.
What can change the subjective impression of "soundstage"(in a very large improper sense), is most of the audible sound. So the obvious solution to factually measure a change, would simply be to record signals and music before and after "burn in" periods, then check for differences. That can easily settle the question of objective change in the sound over time.
What it does not settle is knowing if that change is caused by "burn in"(whatever that really is supposed to mean, as we've already seen anecdotes about guitars...). I've measured significant change over time at magnitudes easily audible with my own headphones, but so far the most obvious contribution to sound change have always clearly been the pads and how they change over time. Because anytime I've tried to record or measure stuff without pads, the differences I so easily found before were gone. Instead I got changes so small that I cannot tell you if it's ambient noise, measurement artifacts, or actual change from the driver's sound.

Thank you for the response. It makes sense.
I've been thinking if it's possible with pure measurements to see it there's a change in detail.
Do you know that and do you have any examples of that?
I just imagine that measurement tests are to see the Frequency response.

 

[gimmeheadroom]

Regardless of whether it's ears adjusting or the headphones/earphones/speakers mechanically burning in, is this real or not based on the science?

For it's absolutely real and has probably nothing to do with the hardware. Like anything else in life the more you experience it the more your mind gets details you missed before. Do books or songs burn in? The more you read the same book or the more you listen to a song the more you pick up.

 

[castleofargh]

Thank you for the response. It makes sense.
I've been thinking if it's possible with pure measurements to see it there's a change in detail.
Do you know that and do you have any examples of that?
I just imagine that measurement tests are to see the Frequency response.

What do you mean by detail? If we measure changes, depending on the amplitude and nature of the change, we may sometimes be able to predict to some extent what type of subjective change will be perceived by a listener(part of a sound engineer's job would be to know most of those, I guess). Like maybe some boost somewhere in the treble will feel to many people like an increase in details. If the sound is getting louder overall(with the pads being compressed and the driver coming closer to the ear over time), that too could perhaps feel like increased details to most people. But recently I've read a post where someone was clearly describing a massive increase in distortions as being more detailed. Obviously I would not say, that in general, increased distortions sound more detailed. Most likely, other people hearing what he heard would not call that more detailed. That's the issue with subjective impressions. They can be really subjective.

 

[Redcarmoose]

With acoustic guitars it's mostly the effect of temperature and humidity changes on the wood. The nut and saddle don't change. Those are bone. But guitar players can be like audiophiles too. There are armchair guitarists who fuss over all kinds of inconsequential things instead of playing and practicing!

That’s so true about a guitar getting acquainted with the humidity and temperature of the house. Who knows what causes the guitar to change after playing. It’s often reported. I’m just as accepting as it being all mental also? It’s also an amazing phenomena about old guitars sounding different than when they were new. Also acoustic guitar manufacturers attempting to pre-age wood by heating and drying it?

Probably the best wear-in proof is jeans and shoes. Though Sony now uses specific capacitors which do actually change over time. Literally in the firmware of the DAP players they make they recommend 200 hours of play before the units are “burned-in”. Also with the ones I have owned it was super noticeable the first 50 hours with dramatic change, until 200 hours when they had the recommended burn-in. They then continue to actually sound better and better, even better at 1000 hours.

 

[bigshot]

Are you saying that firmware breaks in? How is that? I've never experienced any change in performance of solid state electronics unless it gets hot and starts erring. But that isn't a good thing at all.

 

[Goldvein]

What do you mean by detail? If we measure changes, depending on the amplitude and nature of the change, we may sometimes be able to predict to some extent what type of subjective change will be perceived by a listener(part of a sound engineer's job would be to know most of those, I guess). Like maybe some boost somewhere in the treble will feel to many people like an increase in details. If the sound is getting louder overall(with the pads being compressed and the driver coming closer to the ear over time), that too could perhaps feel like increased details to most people. But recently I've read a post where someone was clearly describing a massive increase in distortions as being more detailed. Obviously I would not say, that in general, increased distortions sound more detailed. Most likely, other people hearing what he heard would not call that more detailed. That's the issue with subjective impressions. They can be really subjective.

So would you say that when we say that some headphones are more detailed than others, it's just subjective?
That if you took a cheap headphone and an hd800, then you could not perceive the difference in the detail by measurements? I'm sure that just by looking at driver/voice coil material and size, you could roughly see what driver would create the best detail. But there must be some difference if we measure them. Or is it just the distortion or the lack of it?

 

[Sgt. Ear Ache]

lol, 200 hours of burn in for a DAP. oh boy...

 

[castleofargh]

So would you say that when we say that some headphones are more detailed than others, it's just subjective?
That if you took a cheap headphone and an hd800, then you could not perceive the difference in the detail by measurements? I'm sure that just by looking at driver/voice coil material and size, you could roughly see what driver would create the best detail. But there must be some difference if we measure them. Or is it just the distortion or the lack of it?

No. I'm saying that what some people consider more "detailed" may have nothing to do with fidelity or the actual ability to hear more of the music.
-For fidelity, objective measurements are not only a clear way to tell, it's also the only way.

-For the ability of a listener to notice as much as possible, there is obviously a part related to the listener's hearing and his listening skill. He'd also typically need a frequency response as flat as possible(to his ear if he's using headphones), because of how auditory masking works. Then, as noises and distortions may, when too loud, become the extra sounds that will mask some of the otherwise audible quiet cues, he'd logically want noises and distos to remain a good deal below the signal. So there is certainly a correlation between fidelity and what we can perceive(up to a point!!!!). But just looking at measurements and predicting what someone might consider detailed subjectively, is quite different from those listeners actually being able to pick up more cues in a listening test.

-For someone's impression of details, you can probably get away most of the time with rather crappy fidelity. Maybe just trick people by boosting some key areas of the frequency response to make it seems like some instruments are super clear and crispy. Or even just by tuning the headphone to be overly bright so stuff like instrument location can feel very precise. That would not actually be the most detailed situation, but it would probably feel like it is to many people. because the feeling of details and actual audibility are different, just like how the impression of fidelity and actual fidelity can be very different. or how the impression of big sound changes from burn in, can be very different from the objective sound change over time.

Are you saying that firmware breaks in? How is that? I've never experienced any change in performance of solid state electronics unless it gets hot and starts erring. But that isn't a good thing at all.

No it was yet another weird Sony DAP marketing joke. They mentioned for some DAPs how they were using special capacitors that needed burn in. On some models they also argued that the sound was better because they used like 4 or 8 caps instead of 2 reaching the same total value... And a few years before, they were all about the wires between the battery and the PCB having lower impedance(lower than what? Nobody knows). There was also something about the soldering of that "extraordinary" battery cable being done by hand I think(or was it one of A&K BS marketing? IDK)... Before that, while they had some of the most stable and accessible UI you could find, what they were advertising instead was the karaoke option to display the lyrics (if you added some). It's like a tradition of advertising about the least significant yet peculiar stuff in the entire device.
Remember that Sony also came up with the audiophile SD card, with some graph lacking any relevant scale allegedly showing lower noise measured god knows where, about signal in the Mhz. You know, audiophile stuff. so, capacitors changing over time might just be the most accurate stuff they have advertised in a long time.

 

[HipHopScribe]

If headphone drivers actually underwent physical changes to such a large degree that it was audible after only a couple hundred hours you'd have to replace them every couple years like earpads as that would indicate terrible durability

 

[pinnahertz]

"Burn-in" may or may not be real, depending on the device. "Burn-out" is real, and can occur while attempting over-enthusiastic "Burn-in".

The audibility of "Burn-in" may depend on the device and degree of change. The audibility of "Burn-out" has been proven to be positively identified in a massive series of double-blind tests. In some sighted tests, there was sensory reinforcement from the visual indication of "Burn-out" (smoke/flame). Of a panel of 200 participants, 99% of test participants preferred the system's performance prior to "Burn-out", one participant preferred the end result over pre-Burn-out performance, and one returned a 50% score because his hearing aid was turned off.

When the "Burn-out" phenomenon was tested as applied to power cables, there was additional sensory reinforcement (odor, possible off-gassing toxicity). 100% of panel participants preferred the absence of that stimulus prior to "Burn-out".

The original population sample was 202, but two subjects withdrew from the test prior to its initiation due to personal "Burn-out". No smoke or flames were detected, but one withdrawing subject did present a negative odor.

Of the 200 participating subjects, 30% were professed audiophiles. 10% of professed audiophile participants presented a negative oder bias. Additionally, 4% of audiophiles presented a generalized negative visual bias, but statistical analysis of the results indicates that the negative visual bias was compensated for by several young female test subjects resulting in a null in participant visual bias data. However, the negative odor bias interjected by some participants affected the female population sample to a greater degree, which resulted in a possible uncontrolled bias in the data. It was also found that when test sessions included two test subjects, and one subject was female, 49% of the test subjects tended to ignore visual sensory input of the actual test devices. The cause was not determined, nor to where their attention may have been diverted. In that scenario, 1% of test subjects seemed to ignore negative visual bias of other participants, or even present a positive bias to participants of the same sex. Again, the cause was not determined.

The test data seems to support the general avoidance of "Burn-out" as an action producing greater participant satisfaction.