[turkayguner]

I have never been a believer in breaking-in stuff. There was just one time though. I got the RHA MA750i from the package and plugged it in the phone's out. It was sounding like there was a lowpass filter at around 500Hz. I plugged off and in again, changed tracks but nope it was all the same like filtered out all the mids and highs. I was like what da..?!? And put them off of my ears because I was very frustrated and started digging the internet about issues with MA750. During my research phone was playing through MA750i unintentionally and when I wanted to give it another try, I put them in my ears and was shocked. There were no filtered-like sound anymore. I think it was something with the dynamic driver due to humidity or something. Still not an evidence to break-in though.

 

[abm0]

Zeos' new break-in test of the Sony MDR-Z1R:

A viewer graphed his data here: http://imgur.com/a/qM9aU
The flatter curve is always the compensation or opposite of the changes in FR that had occured after that number of hours.

Looks quite audible, but he didn't account for pad compression, so it's not necessarily indicative of how much the drivers may have changed. :/

 

[castleofargh]

pads were never even a question. they totally matter and absolutely change the sound over time. but to me that's like the filters in my IEM. if changing for new ones reverts to the original signature, should that be called burn in?
isn't burn in about the drivers changing over time?

 

[Strangelove424]

Is this a burn in or a torture test? I wonder if the sound changed over an unrealistically long 100hr cycle due not just to pad compression, but basic mechanical effects like heating up of the voice coil. Would the headphone change through the length of each 100 hr marathon session, regardless of age? And does all of this make enough difference to make judging the headphone impossible?

His headphones do sound good though. Or do mine sound good? Maybe it's his mics. The chicken, or the egg... or the rooster?

 

[frodeni]

I have never been a believer in breaking-in stuff. There was just one time though. I got the RHA MA750i from the package and plugged it in the phone's out. It was sounding like there was a lowpass filter at around 500Hz. I plugged off and in again, changed tracks but nope it was all the same like filtered out all the mids and highs. I was like what da..?!? And put them off of my ears because I was very frustrated and started digging the internet about issues with MA750. During my research phone was playing through MA750i unintentionally and when I wanted to give it another try, I put them in my ears and was shocked. There were no filtered-like sound anymore. I think it was something with the dynamic driver due to humidity or something. Still not an evidence to break-in though.

This resembles my experience as well. I experience a change, but in all honesty, I do not comprehend why I do. It is so bloody hard to describe something I do not understand, and is also a bit socially intimating. Claiming something without even being close to reason for it, to me, often times feels like arguing a UFO sighting.

"Hey, people, listen, this USB-cable is awesome!" It just does not sit well, with my fellow ICT students. It still is my experience: In my experience, there is a distinct difference using different USB cables, and in all honesty, there really should not be. It just makes no sense at all. None what so ever. Signal loss over USB is simply insanely close to zero, it sort of is a stated design goal of the interconnect.

Some argue that humans learns to infer the sound, and improve that skill to infer the reproduction over time. There is probably something to that. I have used my HD800 extensively for two years now, and going back to my Denons, it takes some getting used to. The Denons also resembles the speakers I use, and the cans of my pasts. Yet, all my listening experiences cannot be reasonably explained by just that. I just had a re-solder job done on the cable for the HD800, and actually had to re-do the soldering as there were something completely off by the imaging rendering. After the second resoldering, the renedering appeared substantially improved, and more realistic. There was a completely different rendering of the higher end (the part that my ears are still able to hear though), as compared to my recollection of the rendering before the cable broke.

To me, this resembles my experience with any headphone cable I have broken. The reproduction at the end, actually resembles the reproduction if you use very thin cables, like the ones use in tiny transformers. Like when some slight resistance is added, which would be the physicist in me screaming. (I actually had two classes of physics at the University of Oslo). The thing is, if I tried to measure these cables, I most certainly do not posses any metering device that could tell any difference on this cable. Nor do I believe any instrument at the university would help me any. But I do experience a difference, and simply could not track voices like I used to, for a few days after the last soldering job. Right now, everything is incredibly tight for imaging, and separation is killing it. I just do not know why this is so. In one instance, I simply cannot separate instruments properly, and voices appear smudgy as for imaging. (not precisely placed on the soundstage). After a few days, everything falls into place.

What troubles me, is the insane number of soldering points inside the HA-1 of mine. That is a lot of mess, for just one soldering point. The implications are sort of mind blowing, if there is anything to this.

"Go For Broke" by MGK and James Arthur was puzzling. There's just so much multi dubbing of voices in that tune, and this soldering thing threw this completely off for me. I could not trace the voices properly. It improved by time. At times there is at least quadruple recordings of Arthur. Really funky artistic work, at least to me.

Do I claim that I know that the soldering needed to burn-in? No. Not really. But I am experiencing a clear shift in my skill as a listener after this soldering job. My claim is that I do have that experience, and that I know the physics, even have some schooling on it, yet I have no real explanation for my experience. Also, the physics appears dead sound. To me, there is a lack of understanding, bridging the gap of theory and experience. It is also bloody hard to describe what I am sensing, as the reasonable part of my head is screaming that this simply should not be. Yet I cannot escape, that this is, to me, a real experience. Bewildering as it is, describing it precise is hard.

Does the measuring in the OP answer any of my questions? No. There is a ton of people who report to experience what we are not even close to measure. Not much news in this test really. No smoking gun at all. The gap between experience and theory, is simply not closed merely by restating the obvious and the known.

 

[Ramblinman]

Quote:


Nope, if the diaphragm and voice coil in a headphone driver loosen up it's broken. Headphone drivers are not like loudspeaker drivers, there's no big movement, actually there's hardly any movement at all unless you really crank the volume.

This seems very counterintuitive. Any diaphragm type device will loosen up just through regular use and very well may become more effective when it becomes more flexible. Not the diaphragm itself necessarily, but the surround or other portion that allows it to move and reset. I would think bass response would benefit the most (just thinking logically) because it takes greater movement of a diaphragm to create it. Even if the movement is small, the easier the diaphragm is to move the more efficient it will become.

But, then again, what I am describing sounds more like "break in" (like a baseball glove) than "burn in" which sounds downright destructive

Am I way off base here?

 

[bigshot]

If a transducer isn't anchored properly the sound can certainly go to pot. But manufacturers aim for consistent performance, so they design the excursion so it doesn't change over time.

 

[jagwap]

This seems very counterintuitive. Any diaphragm type device will loosen up just through regular use and very well may become more effective when it becomes more flexible. Not the diaphragm itself necessarily, but the surround or other portion that allows it to move and reset. I would think bass response would benefit the most (just thinking logically) because it takes greater movement of a diaphragm to create it. Even if the movement is small, the easier the diaphragm is to move the more efficient it will become.

But, then again, what I am describing sounds more like "break in" (like a baseball glove) than "burn in" which sounds downright destructive

Am I way off base here?

You are not way off base. The problem here is that this does not show up in frequency response curves to any great extent, so it will not be believed here by many.

Any mechanical system can exhibit break in. But with high quality materials the measured performance will not be obvious until you look in more detail. Google: driver break-in klippel. Klippel make measurement equipment which can measure the change in stiffness of the driver parts through laser interferometry. They are not a psudo science outfit, but the most respected driver measurement manufacturer in the world. Their articles discuss this.

There is more to audio than frequency response.

 

[bigshot]

If performance changes over a period of a week or two, how do you keep it from continuing to degrade? Maybe headphones could come with expiration dates... replace after 500 hours. That sort of thing.

 

[Ramblinman]

You are not way off base. The problem here is that this does not show up in frequency response curves to any great extent, so it will not be believed here by many.

Any mechanical system can exhibit break in. But with high quality materials the measured performance will not be obvious until you look in more detail. Google: driver break-in klippel. Klippel make measurement equipment which can measure the change in stiffness of the driver parts through laser interferometry. They are not a psudo science outfit, but the most respected driver measurement manufacturer in the world. Their articles discuss this.

There is more to audio than frequency response.

Exactly, if there weren't, tube amps would sound like garbage.
They certainly don't measure well typically.

 

[bigshot]

Tube amps can certainly sound as good as solid state amps. It's just easier and cheaper to make great sounding solid state amps. Most solid state amps perform far beyond the threshold of audible transparency. They measure better, but they don't necessarily sound better because your ears have limitations.

 

[Ramblinman]

Tube amps can certainly sound as good as solid state amps. It's just easier and cheaper to make great sounding solid state amps. Most solid state amps perform far beyond the threshold of audible transparency. They measure better, but they don't necessarily sound better because your ears have limitations.

totally agree, my point is that they typically do not measure very well on conventional measuring equipment even when they sound great. IMHO they often sound better than solid state.

 

[jagwap]

If performance changes over a period of a week or two, how do you keep it from continuing to degrade? Maybe headphones could come with expiration dates... replace after 500 hours. That sort of thing.

It is asymptotic. The burn in is a deminishing return until a steady state is achived. Of course the driver can also wear out, but the time frame for that is so much longer it has a miniscule contribution until near end of life occurs.

Now a good design team will not attempt fine tuning until break-in is completed (at least 90%), so that the production units will also end up sounding as desired.

I have worked at numerous audio companies, and ALL of them break-in drivers before tuning, or validation. There always seems to be a pair of speakers, face to face and out of phase facing each other (cancelation lowers annoying sound leakage) with music playing each time you head home.

 

[bigshot]

Who says burn in hits a static state? Change is change. If it changes, odds are it will continue changing. If burn in was a real thing, the manufacturer would burn in and test before they shipped, wouldn't they? I think burn in is just an excuse to get consumers to exceed their return window.

By the way, I was part of a test group for a darn good set of headphones, and they sent us copies to evaluate that were fresh off the boat. They didn't tell us to burn them in before evaluating. I tested two copies- one prototype that I had been using for a couple hundred hours over a period of weeks and one that was fresh out of the box from the production run. They both sounded exactly the same. I ran a tone sweep on them and they were identical.

I do think it's a good idea to run audio equipment a while when you first get it. If something is going to fail, it will likely do it sooner than later, and if it fails fast, it's easier to return. That is probably the core of the idea that got conflated with trying to get people to exceed their return window to create the myth of burn in.

 

[jagwap]

Who says burn in hits a static state? Change is change. If it changes, odds are it will continue changing.

I said it is asymptotic, so it iterates to a final state. If you want to be pedantic (really? Here in this forum?) Then this means continuously changing, but less and less per unit of time until failure. But at some point the change settles to an amout undetectable.

If burn in was a real thing, the manufacturer would burn in and test before they shipped, wouldn't they? I think burn in is just an excuse to get consumers to exceed their return window.

They do not need to as burn in does not affect basic functional testing enough to stop the test asserting the unit is good.

By the way, I was part of a test group for a darn good set of headphones, and they sent us copies to evaluate that were fresh off the boat. They didn't tell us to burn them in before evaluating. I tested two copies- one prototype that I had been using for a couple hundred hours over a period of weeks and one that was fresh out of the box from the production run. They both sounded exactly the same. I ran a tone sweep on them and they were identical.

I do think it's a good idea to run audio equipment a while when you first get it. If something is going to fail, it will likely do it sooner than later, and if it fails fast, it's easier to return.

Agreed, this is a good policy. Many manufactures cannot afford to do this, but high end products may be run for up to 24 hours to catch the unfortunately named "infant mortalities". This also serves to do most of the break-in. Perhaps the headphones you tested above had this as a standard test in manufacture?

That is probably the core of the idea that got conflated with trying to get people to exceed their return window to create the myth of burn in.

Google the terms I put in the above reply.

Break-in is not a myth. There are many myths spoken about it, but it exists.