[bigshot]

I missed this one before because I stopped reading after my first reset button was pushed...

Tyll, who was able to reliable tell a difference (albeit small) between a brand new pair and a "burned in" pair

First of all, that isn't the Oppo PM-1s. The Oppos were designed to perform to spec before and after burn in and they did. A +/-1dB difference isn't likely to be audible in normal use. The designer at Oppo told me that the typical manufacturing tolerance for good headphones is +/-3dB. So the ones that Tyll compared may very well have been as much as 6dB apart from the start. A frequency response variance of 6dB is most likely clearly audible... and the cans Tyll tested may have been that far apart from the start before they were even broken in. For Tyll's test to mean anything, they should have tested both sets against each other either both not broken in or both broken in to determine if that difference was a part of manufacturing standards. You can't say that burn in was responsible for the differences unless you set a baseline proving that they were either the same at the start, or the same after burn in. Otherwise they could just be two completely different sounding sets of cans.

 

[jagwap]

I'm asking for explanation, not a brush off. If you aren't interested in having a conversation, there's absolutely no reason to post at all. Have fun with your experts.

I have had hundreds of conversations with you. I have had this one with you before. I was busy and I feel that even after repeat many points, like the one below about frequency response, I am not being heard. I just suggested in limited time, you go look up the previous time we discussed this and you ignored me.

I have to say, when I see people stating things without any explanation and using irrelevant analogies to automobiles and machine parts, it makes me thing this whole thing is totally made up. I'm open to it being a real thing, but someone would have to be able to point to a headphone that is clearly different after burn in with controlled listening tests and measurements. That isn't asking too much. Those are the tools we use to evaluate every aspect of audio fidelity.

If you're saying it doesn't affect the frequency balance, that goes against everything people say about burn in. The anecdotal reports say that headphones sound thin and open up with a fuller sound after burn in. That is definitely describing a change in response.

No, it isn't. If frequency response is the only thing you can adjust, and measure, then it is the only tool you can see. Once you get access to transient response, group delay, transient intermodulation, and countless others, your horizons broaden. But for those, you need to be able to design the product.

At least I'm willing to discuss the possibility that I might be wrong.

It doesn't actually come across that way. You regularly state you want to know about product that sounds different, as everything you have heard sounds the same. It really sounds like you have already made your mind up, which doesn't belong in a science forum. You are given papers on other measurements, and repeat it must be frequency response.

 

[jagwap]

I missed this one before because I stopped reading after my first reset button was pushed...



First of all, that isn't the Oppo PM-1s. The Oppos were designed to perform to spec before and after burn in and they did. A +/-1dB difference isn't likely to be audible in normal use. The designer at Oppo told me that the typical manufacturing tolerance for good headphones is +/-3dB. So the ones that Tyll compared may very well have been as much as 6dB apart from the start. A frequency response variance of 6dB is most likely clearly audible... and the cans Tyll tested may have been that far apart from the start before they were even broken in. For Tyll's test to mean anything, they should have tested both sets against each other either both not broken in or both broken in to determine if that difference was a part of manufacturing standards. You can't say that burn in was responsible for the differences unless you set a baseline proving that they were either the same at the start, or the same after burn in. Otherwise they could just be two completely different sounding sets of cans.

That is too simplistic an answer. Typical is +/-2dB in the midband, and larger variations towards the frequency extremes. However any decent manufacturer can manage +/-1.5dB without trying too hard, if they push for greater control. So I think you are assuming too much about Tyll's circumstances with high end headphones.

 

[elmoe]

I'm sorry, but when the alternative is no testing at all, imperfect testing is suitable for the time being. You asked if there had been any tests done comparing headphones pre burn in to phones post burn in. The answer is yes, there has been.

I'm suggesting that burn in is probably a myth - in response to the question posed by the thread title. I've presented an article that does some fairly rigorous tests on 4 different models of headphone and that concludes that burn in is probably a myth. If you don't want to advocate in favor of burn in, then there's no need for you to respond. If you do wish to advocate in favor of burn in...show me something better than what I presented.

There's plenty of things that the human body tests better than machines. Which is why the type of testing is important. Measuring responses is nice but ultimately until I see the result of a proper, volume matched, double blind ABX listening test, I won't be convinced either way. I can respond to you if it pleases me, because I'm suggesting your suggestion is not founded in enough valid evidence to be a fact. Feel free to ignore my post and move on.

Uh oh. You just went from "show me one example" to "one example isn't enough". Obviously no one is going to be able to prove a negative with every set of cans in the world. That just isn't possible and it isn't reasonable to demand that. It's better to try to prove burn in exists. Can you show me evidence that burn in is audible to human ears with any headphones under a controlled listening test? I'd be interested in seeing that. (remember when you answer that you already said you didn't know of any.)

No. I asked for a proper example, I haven't seen one yet. All the articles and examples posted in this thread so far have shown some differences, with some tests where people could reliably tell the burned in headphone from the brand new one in listening tests. If you have more reliable data to share, I would love to see it.

When you ask if I can show you evidence that a burn in is audible to human ears with any headphones under a controlled listening test, that's what I've been asking this whole time. You've been in this thread since day 1, I just got here.

lol. OMG. The test was only "bad" according to you and because it didn't conclude what you wanted it to conclude. If you have something that is at least as good that indicates burn in is real, present it. Until then...I win.

I don't want to test to conclude one way or the other. Makes no difference to me if burn in is real or not. At the end of the day I don't burn in anything unless I'm using it to listen to music. If it happens great, if it doesn't great. The sound I hear won't change either way.

salient point. That ritualistic quality is pretty appealing. Setting up your little burn in station and then waiting for the process to complete at which time you get to audition those sweet burned-in phones...it's like brewing up a good beer or something.

That's the dumbest thing I've ever heard. Why would you find it ritualistically appealing to waste electricity by over using your gear? I've never heard of anyone who was 100% convinced burn-in was a thing who didn't feel inconvenienced by it.

 

[bigshot]

I have had hundreds of conversations with you. I have had this one with you before. I was busy and I feel that even after repeat many points, like the one below about frequency response, I am not being heard. I just suggested in limited time, you go look up the previous time we discussed this and you ignored me.

I'm having a conversation HERE. I'm not running off to any website people point me to. That's been a fool's errand in the past (especially with that turntable guy!) and my time is valuable too. If I am discussing something I want to be able to ask questions. I can't ask questions of a link. I politely asked you...

If it isn't frequency response making it audibly different, WHAT is it and how is it measured?
What's the audible threshold?

I made it nice and big so you can quickly cut to the point and not waste time. Sound is made up of frequency and amplitude, the modulations are laid out in time. If something is accurately reproduced, it has low distortion. If it isn't accurate, it has high distortion... dynamics, flutter, noise floor... Just answer simply and clearly.

I am not ignoring you or even disagreeing with you. I am CHALLENGING you, and you are bluffing and refusing to commit. If you continue to dodge the question, I'll send you off to a link to tell you what I think of your lack of reply.

You have plenty of time to thread crap, but not enough time to deal with honest questions. We're having a conversation here. If you don't have time to participate, the door is one click away. Don't let me stop you. If you have more important things to do with more important people, by all means go do it.

That is too simplistic an answer. Typical is +/-2dB in the midband, and larger variations towards the frequency extremes. However any decent manufacturer can manage +/-1.5dB without trying too hard, if they push for greater control. So I think you are assuming too much about Tyll's circumstances with high end headphones.

GREAT! Something we can work with!

What would be the sample error parameters for the headphones Tyll was saying he could hear burn in with? Would that sample error be audible from one set of the headphones Tyll tested and another of the same make and model? Is a deviation of +/-1.5dB audible? These are pertinent questions. I would be happy to assume that the cans Tyll was comparing had a sample deviation of +/-1.5dB. And I would also be happy to say that a deviation like that might be audible if it was in a certain frequency range and deviated in different directions in the two sets of cans. That might invalidate his test, wouldn't you agree? It would have been better if he tested them both in the same state first to make sure it wasn't just manufacturing differences.

But you've gotten us talking about frequency response again... You realize that, right?

 

[bigshot]

When you ask if I can show you evidence that a burn in is audible to human ears with any headphones under a controlled listening test, that's what I've been asking this whole time. You've been in this thread since day 1, I just got here.

Spoiler

We haven't seen anything to indicate that aside from anecdotal impressions and casual comparisons.

I spoiler tagged that because I didn't want to ruin the end of the story for you. If you don't know which way the river flows, you may not want to wade in too deep.

Oh I forgot one...

Spoiler

...and people who make claims but are just too busy to take the time to explain them.

 

[elmoe]

Spoiler

We haven't seen anything to indicate that aside from anecdotal impressions and casual comparisons.

I spoiler tagged that because I didn't want to ruin the end of the story for you. If you don't know which way the river flows, you may not want to wade in too deep.

Oh I forgot one...

Spoiler

...and people who make claims but are just too busy to take the time to explain them.

I've made no claims for or against. Basically you're telling me there is no evidence of burn in existing and very circumstancial evidence of it not existing. Got it.

 

[castleofargh]

@bigshot if I may, we did have that conversation at length with @jagwap already(maybe a year or 2 ago?) and the data from the speaker manufacturer was also brought up and discussed a bunch.
the question of audibility is always tricky, and my very personal opinion is that slow progressive change over time is going to go unnoticed unless the total turns out to be massive. which isn't something supported by measurements so far. as the most massive change I've seen comes from pad wear and placement of the headphone on the head. 2 phenomenons I don't consider part of "burn in". so my guess is that people feeling changes do so because of occasional big contrast in sound(we haven't tested all gears, maybe some do have terrible stability over time?), or even more likely, erroneous memory of the original sound.

but that's only my point of view and educated guess. what happens should be confirmed by reliable data instead of opinions and poorly controlled anecdotes. in that respect, I don't see why your testimony is more reliable than someone's testimony that he heard a clear change between 2 pairs of headphone. in both cases we're dealing with one anecdote, one listener. and the amount of actual controls aren't amazing. my point is, just because I agree with your conclusion, doesn't mean I have to agree with how you reached it.

 

[bigshot]

@bigshot if I may, we did have that conversation at length with @jagwap already(maybe a year or 2 ago?)

I'm afraid that the way my brain works, without a face or name or formal introduction, everyone blends online into an undifferentiated whole. Once we are properly introduced, I can connect stuff. Sorry about that! Feel free to remind me of who you all are. (I've been nicely introduced to you Castle.) I remember hearing something about speaker tests, but it was all hush hush and couldn't be shared, so I dismissed it as being bluff.

I'm not big on what *seems* correct. That has led me astray too many times. I prefer solid evidence pointing in one direction or another. I really don't care which direction that is, but when solid evidence points in a particular direction, I tend to aim that way myself, even if that doesn't make sense. That gives me the opportunity to do more research and make sense of it.

 

[jagwap]

I'm afraid that the way my brain works, without a face or name or formal introduction, everyone blends online into an undifferentiated whole. Once we are properly introduced, I can connect stuff. Sorry about that! Feel free to remind me of who you all are. (I've been nicely introduced to you Castle.) I remember hearing something about speaker tests, but it was all hush hush and couldn't be shared, so I dismissed it as being bluff.

I'm not big on what *seems* correct. That has led me astray too many times. I prefer solid evidence pointing in one direction or another. I really don't care which direction that is, but when solid evidence points in a particular direction, I tend to aim that way myself, even if that doesn't make sense. That gives me the opportunity to do more research and make sense of it.

I'm afraid I cannot agree to a formal introduction without a chaperone. I'm not that kind of girl. (I am also obliged to take care what I say about my work, who I work for, or stay anonymous online as I have said before)

So when I mention results, I may not be allowed to publish them without a huge amout of approval from corporate. Some of this stuff was 20 years ago.

I have worked with, and continue to work with some of the best in audio design in the world. Everyone agrees: audio is not finished yet. We don't know everything.

 

[bigshot]

I'm duly impressed with the quality of your co-workers. But I'm afraid I've been around this block before... If someone in a public internet forum claims to have special knowledge, I'm not just going to blindly trust them and take their word for it. Get back to me when you can explain how you back up your claims. I'm here for information, not to just have conclusions spoon fed to me. You might be absolutely correct, but if you aren't allowed to talk about it, I don't see why you're talking about it at all. It just makes you look like one of the chumps that comes into this forum with a chip on their shoulder who try to bluff their way through "scoring a point" against "those a-holes in Sound Science". We've been bluffed too often around here.

 

[bigshot]

I've made no claims for or against. Basically you're telling me there is no evidence of burn in existing and very circumstancial evidence of it not existing.

I gave you an example of a high end headphone manufacturer whose lead designer said burn in isn't necessary... and tests by three separate people in three different ways showing tha three different copies of these headphones that were tested sounded and measured basically the same, whether burned in or not.

I'm not going to pay any attention to your bluff either. If you have evidence, present it. If you don't have anything to back up your opinions, then I'll take that into consideration when you express one.

You get your turn at bat. If you strike out, don't blame anyone else but yourself.

 

[elmoe]

I gave you an example of a high end headphone manufacturer whose lead designer said burn in isn't necessary... and tests by three separate people in three different ways showing tha three different copies of these headphones that were tested sounded and measured basically the same, whether burned in or not.

I'm not going to pay any attention to your bluff either. If you have evidence, present it. If you don't have anything to back up your opinions, then I'll take that into consideration when you express one.

You get your turn at bat. If you strike out, don't blame anyone else but yourself.

What bluff is that? I posted in here to see specific data about listening tests, the data I saw was ambiguous at best, it's always "There are slight changes but we guess they're not audible by the human ear and if they are, the changes are so little it wouldn't matter". That's an opinion, not a fact. Can you show me scientific data showing accurate measurements of differences in sensitivity to sound that clearly shows that the human ear indeed is not sensitive enough to easily pickup these kind of changes?

I came here to discuss the "evidence" posted, if you want to argue semantics and call people bluffers, fine by me, I will move on. I'm not here to prove anything, only gather information, which is frankly lacking in this thread.

 

[bigshot]

You're bluffing because you keep moving the goalposts and demand more proof from other people than you do of yourself.

My evidence: A designer of high end headphones who said that burn in wasn't necessary, I provided info on three sets of the same make and model of cans that all sounded the same and performed to identical spec, new and old in three different tests.

Evidence to the contrary: Anecdotal comments by salesmen and customers with no attempt at measuring or applying controls to their listening.

 

[Sgt. Ear Ache]

you're playing games my friend. You aren't interested in receiving information.


The changes you refer to from the article I linked to were smaller than the sort of changes one would get from simply re positioning the phones slightly differently on the listener's head or from environmental changes. If the changes resulting from supposed burn in are that tiny, how could you or anyone consider them meaningful. That's aside from the fact that as I indicated earlier most of the small changes evident n the tests went up and down repeatedly - again not what burn in is supposed to do.

If you want to argue in favor of burn in (and you obviously do) then you go out and prove that the tiny changes found in the tests ARE audible. Several of us have done WAY more than enough on our side of the coin.