[bigshot]

Would you say there's a 50% or greater chance that the K701's tested sound different now then at the beginning of the testing, given the graphs posted?

I already said that one test isn't enough to base an estimate of probability on. I would say that your K701s likely sound audibly different than the ones they used in that test. Most headphones are manufactured to about a +/- 3dB response tolerance. It's quite likely that one set of K701s would sound different than another. I wouldn't be able to give you a percentage on that, but it wouldn't surprise me if it is the case.

If those measurements are accurate, it would be useful to continue measuring those cans. I would bet if they shift signature consistently for a couple of hundred hours, they will continue to shift. Another option is that the ear pads might have broken in. Have you noticed a change in the pads since you got your headphones? Do they fit better now?

 

[tansand]

Ack, I'm sorry I gave the impression I have K701! I haven't paid a whole lot of attention to the K240, I haven't noticed any pad changes, maybe they're softer. I think they're the same pads as the K701. Honestly they are not my favorite, but they are better than the Grado SR60 I bought first.

By 'mine' are already broken in, I meant the Soundmagic E50 I listen to most, at the beginning they had a lot of bass, but they settled in and sound more flat now (lmao). I'm so sorry I made what I was saying so unclear!

 

[bigshot]

I don't have in ear monitors, so I'm not up on them... but does the angle and depth you put them into your ear affect the sound quality at all? If so, which frequencies are most affected? Were these your first in ear monitors? How do they customize the fit to different people's shaped ears?

 

[tansand]

......

 

[tansand]

....

 

[bigshot]

I have a kickass speaker system, so I don't really need a lot of cans. If I need them, I have Oppo PM-1s and beater mono price cans for work. The tips make a difference? If you use three different ones and they affect the bass, are you sure the change in bass is due to burn in and not just comparing the sound of different tips at different times?

 

[tansand]

.....

 

[castleofargh]

I'm generally interested, but not greatly motivated. Mine are broken in, like the K701's are. Would you say there's a 50% or greater chance that the K701's tested sound different now then at the beginning of the testing, given the graphs posted?

how would anybody find a percentage of chance from 1 test with incomplete controls?

you asked about "my" pad idea. here is my "super short not burn in experiment 2018".

the shape reminds you of something? ^_^
maybe something like this

did I just replicate the experiment and prove driver burn in?
sorry no.
I placed my on ear BT headphone on my measurement thingy(minidsp EARS), and just took a few measurements over 90mn of time. touching nothing, and playing no music, just letting the natural clamping force of the headphone do its thing on the pads.
if you click on the graph, at the bottom you have a t value giving the time in minutes for each color. the reference(flat) is as I said 90mn.

the headphone is 2 or 3 years old and get some use so long as it's not too hot outside, so I'd say, well burned in^_^. so the pads are far from brand new, but I still got enough changes to make my point I believe.
I applied differences like Tyll did using the last measure as reference of flat.
I zoomed on the 3khz-20khz like he did. and voila!

 

[tansand]

I like it! Thank you for getting back to me.

There are two differences. First, the time. What you have shown happened over 90 minutes not 90 hours. And, the peaks are reduced more than the nulls, while the K701 test the peaks and nulls reduce evenly. Did you notice my experience above?

The foam tips have a very even sound, I think the lack of leaks flattens the frequency response in the highs as well as the bass. That's what I hear.

This supports your pad theory, too.

 

[castleofargh]

oh of course, the time is different, the magnitudes, the headphones are different. I measured in totally different conditions using different gears. I'm certainly not claiming it's identical, only that the similarities do give a few points to team pads and my argument that it's a bad way to show data. if I have to claim only one thing, it's that the pads need to be removed to test driver burn in, otherwise we'll never know which part of the variations came from the driver itself.

about the reduction being more important for peaks, sadly it's again just a game of representation. the actual data doesn't care. I just didn't bother to align the frequency responses before applying the difference to get this resulting graph. while Tyll did align all the graphs at 300hz(meaning 300hz is at zero for all measurements). imagine what he did, he made a graphic representation of differences between measurements, but before showing the results, he changed the values of those difference based on a a frequency he hand picked. that's double wrong. I imitated his presentation really just to show that it's misleading and not really evidence of burn in. it's better not to legitimize anything presented that way, be it his or my graph.

just raw measurements would have made so much more sense. although they probably wouldn't have helped make a case for burn in. but at least we could have observed the variations as they really occurred. I guess it would mostly have showed the sound getting louder and some small variations due to the position of the driver respectively to the ear, and the reduction in volume of the acoustic chamber. or maybe the pads making a better seal so the subs would increase. that sort of stuff where driver burn in wouldn't be the first suspect. of course we can't exclude burn in based on such experiences, but we also can't really say they show it to exist.

-------------------------------------------------------------------------------------------------------------------------------------------------------------------
tips affect the sound, in how they extend the tube of the IEM, to how they occupy more or less space in the ear canal, and also a little by how they're shaped or how much they will absorb and reflect sound. that's very easy to measure, the only issue being that the measurement defines the sound as experienced by the mic. once inserted differently in my ears, the result will be different. so I don't believe we should rely on measured differences to say how some tips will sound when used on us. but at least measurements can confirm that there are indeed differences measured simply by having different tips.
I think foam tips have better chances to allow for a fine seal, while silicon may go from impeccable seal and more subs than foam, just leave a clear gap and rolled off subs if pressed the wrong way by the ear. maybe for that reason we can expect a little more stability in the subs with foam? but an even sound, IDK. different IEMs will have different responses and I'm not sure foam tips are a panacea. the trebles will be affected a good deal by almost anything, starting with insertion depth, so I won't even try to guess something in that area. I really don't know.

 

[jagwap]

I think the title of this thread is misleading. Nothing final yet.

This is about speaker drivers, but is interesting:
http://www.gr-research.com/myths.htm
Edit: and this:
http://www.gr-research.com/burnin.htm

 

[bigshot]

With 1200 dollar magnetic planars and monoprice beaters, I guess I'm not surprised you don't hear break in . Do you have others, How many headphones have you owned?

I have a set of Sennheiser HD590s around here somewhere. They got put in the drawer when I got the Oppos. I had some AKGs a million years ago. Senn PX-200s for portable... I think I had Sony cans at one point too, but I don't remember the model. I'm not big on churning my equipment, so my sample size for cans isn't as big as those who have a few dozen pairs. But because I'm not swapping sound signatures all the time, I am probably more focused on the fine points of how a particular set of headphones sound. I also am extremely picky about response curves and I've trained myself to EQ. That might help in being able to identify changes too. If something had shifted, I would have known it.

Here's what I've been listening to lately...

I think the title of this thread is misleading. Nothing final yet.

You can't prove a negative result I guess.

 

[jagwap]

You can't prove a negative result I guess.

You have repeatedly claimed to have proved a negative: that all uncoloured DACs sound the same. Also from memory I think you agreed with the regulars here that 44..1khz/16bit cannot be distiguished from higher resolutions, also stated as a proved negative. So I'm surprised to see you write that you cannot prove a negative, as you have spent so muct time and effort on doing excactly that.

So, and this us the wider audience in sound science, now I have given three examples from two sources (including the paper from Klippel further up the thread) of measured differences in speaker drive units, do you still have the stance that run-in/burn-in/break-in cannot exist? True a woofer is larger than a headphone driver, but a sensible argument is that the effect scales, rather than disappears.

A 10-20% change in Fs is not trival, and that is just one parameter. Lets have a better debate on this.

 

[castleofargh]

I think the title of this thread is misleading. Nothing final yet.

This is about speaker drivers, but is interesting:
http://www.gr-research.com/myths.htm
Edit: and this:
http://www.gr-research.com/burnin.htm

I made the same observation about the title. with all the gears, all the sizes, materials, etc. it's a little silly to use one weak experiment on one pair of headphones and call it a final verdict. Tyll certainly didn't say anything of the sort. only OP read what he wanted in the article.

maybe this will look like another attempt to reject facts, but I believe speakers shouldn't be mixed with headphones for this. I happen to believe that speakers do change over time. belief I hold because I've seen consistent evidence suggesting that much on more than one model of driver. but so far I can't say the same for headphones where what little evidence I've seen was unclear or showing tiny changes that could pretty much have come from anywhere. as for IEMs, just the way to measure them has consistently given me more variations than any apparent change in the driver itself. be it on dynamic or balanced armatures.
so I came to think that size does matter. ^_^
also it's fairly obvious that the amplitude of movement, the air that needs to be moved, the forces exercised on the diaphragm, they all tend to be significantly bigger on speakers. so I'd expect mechanical wear to be more noticeable there.
I see speakers as a good case to say that indeed something can happen over time when stuff are pushed and bent, which really nobody can argue against. but it will give a false idea about the magnitudes involved in most headphones. people shouldn't expect the sound of a headphone to somehow clearly transform on a new pair thanks to "burn in". that's just poor thinking given the actual evidence we've had so far.
until I see at least some evidence of the contrary on at least a few pairs, I'll keep suggesting placebo, new toy effect(getting used to the gear and signature), non perfect memory(how dare you?), taking some time to find the best placement on our head, and of course my friends the pads wearing off and maybe conforming a little bit to the shape of our skull over time, as the more relevant and more likely causes of perceived change on headphones and IEMs. and TBH even on speakers, I wouldn't blame driver burn in for my feelings of change in sound. at best I'd admit it can be part of the causes. which is a long way from guys coming here saying "I felt a change in headphone X, so I know burn in is real".

 

[jagwap]

I made the same observation about the title. with all the gears, all the sizes, materials, etc. it's a little silly to use one weak experiment on one pair of headphones and call it a final verdict. Tyll certainly didn't say anything of the sort. only OP read what he wanted in the article.

maybe this will look like another attempt to reject facts, but I believe speakers shouldn't be mixed with headphones for this. I happen to believe that speakers do change over time. belief I hold because I've seen consistent evidence suggesting that much on more than one model of driver. but so far I can't say the same for headphones where what little evidence I've seen was unclear or showing tiny changes that could pretty much have come from anywhere. as for IEMs, just the way to measure them has consistently given me more variations than any apparent change in the driver itself. be it on dynamic or balanced armatures.
so I came to think that size does matter. ^_^
also it's fairly obvious that the amplitude of movement, the air that needs to be moved, the forces exercised on the diaphragm, they all tend to be significantly bigger on speakers. so I'd expect mechanical wear to be more noticeable there.
I see speakers as a good case to say that indeed something can happen over time when stuff are pushed and bent, which really nobody can argue against. but it will give a false idea about the magnitudes involved in most headphones. people shouldn't expect the sound of a headphone to somehow clearly transform on a new pair thanks to "burn in". that's just poor thinking given the actual evidence we've had so far.
until I see at least some evidence of the contrary on at least a few pairs, I'll keep suggesting placebo, new toy effect(getting used to the gear and signature), non perfect memory(how dare you?), taking some time to find the best placement on our head, and of course my friends the pads wearing off and maybe conforming a little bit to the shape of our skull over time, as the more relevant and more likely causes of perceived change on headphones and IEMs. and TBH even on speakers, I wouldn't blame driver burn in for my feelings of change in sound. at best I'd admit it can be part of the causes. which is a long way from guys coming here saying "I felt a change in headphone X, so I know burn in is real".

Reasonably argued, but it is equally easy to argue that if a headphone driver of a fifth of the diameter has a fifth of the mechanical movement, with have a fifth of the burn-in effect. That in turn may be proportional to the size of the output, resulting in a similar effect to that of a speaker driver. As you say, no one here has presented the hard evidense yet.

I returned a pair of headphones and got a brand new replacement. The difference was noticable. So I tried the demo pair, which sounded like I remember my broken pair sounding. I know this is inadmissible evidence here m'lud, and it could be down to tolerances, but it could be break-in.

Oh and anyone who accepts +-3dB tolerance on a decent headphone in the midband is not very fussy. +-1.5dB is a reasonable tolerance except the frequency extremes, and manufactures can do better if they spend the money.