How many of you actullay believe IE8 burn in effect? - Page 10

Well first we would have to determine that there was no difference between them to start with. Given the usual production variances it's likely that the two will not start out sounding exactly alike. Notice, for instance, the clearly visible differences in the response of brand new HD800's as published in another thread on this forum.

They would also have to be sure that the person listening could not know which one she or he was listening to.

The funny thing about burn-in is that its always describes an improvement even if its two apparently contradictory processes. Sometimes fat bloated muddy bass (IE8) tames down, tightens and cleans up. Sometimes week bass is said to open up into something more powerful and impacting (RE0?). This seems to describe two contradictory processes both attributed to the benefits of burn-in. Something smells a bit bad about these claims.

Another implicit dubious assumption that I'll mentioned here (and why not throw gasoline on this fire?) is that all IEMs of the same make/model should and do sound the same. People report their different experiences as if they were all listening to the exact same set of phones. Why not suspect that there are some duds out there? I've heard two of the same make/model that sounded different to me. Seems that everything else shows variance in manufacturing quality. Why not earphones? Some cars are lemons right? Why not earphones too? Insofar as the manufacturing process involves any kind of variance the quality of the sound reproduced can likewise vary too.

thwood3...

I think you need to read my post again, I gave two examples of burnt out... what goes up must come down!

You are right about production variances, they do happen. Still, even back in the 1970's the BBC LS35A specification required that any given production unit must be able to be paired with any other production unit and provide stereo imaging to a defined (and very good) accuracy. Whether such accuracy could be applied to the manufacturing of such a tiny transducer as an in ear monitor I do not know.

In any event before comparing a "burned in" vs a non "burned in" unit we would have to first ascertain that the two units could not be distinguished in a double blind test when they were both brand new.

It isn't all that easy to do a true double blind experiment on transducers. The required switching times for example are rather large, and that by itself reduces the sensitivity of such a test. It would be easier to compare the frequency curves of a single unit both before and after "burn in".

I find it rude that someone on generic scientific arguments claims people here are imagining things.

Ed, get a grip man!! seriously, you are like a rabid dog replying to every comment made in this thread whether it is directed at you or not. you seem to have an answer for everything except you proof that it doesnt exist. I have posted in here that I feel it is a mixture of the 2 both psychoacoustic and electromechanical; but you seem to think that your opinion amounts to empirical evidence.

Why would a company make a certain model of an iem or a headphone and not make them sound identical? I can understand that there will be some differences during the length of duration of production, but come on, how much difference would you expect to hear? If each production unit of the same model would sound different than the reputation of the manufacturer would be at serious risk. Of course the the evidence is anecdotal but nobody is arguing about that. What is interesting is that many people have similar experiences with the IE8 in specific. I have never heard about the Shure SE530's improving drastically after some "burn-in". I used to own the SE530's and they sounded the same for the year that I owned them. Why would my brain/mind not be able to detect differences over time with the SE530 but was able to pick up some major differences with the IE8? It is not consistent with the mind adjustment theory. Conducting tests concerning mental adjustment would only result in anecdotal evidence simply because the mind is not able to be quantified during an experiment. You lean towards a theory that can only provide anecdotal evidence. The "burn-in" theory at least can be quantified in a frequency response curve. If the curve does change after some "burn-in" then it would qualify for empirical evidence.

Regarding burn in, I do feel feel my UM3X, the one people agree not to affect by burn in, changes. Not only it change better, sometimes it become worse.

Simple example, I used to listen to my Korg Mr-1 with UM3X, I can hear sibilance. Around 350-400 hrs, the sound seems suddenly muffled in all spectrum, sibilance is gone as well, so I just let it keep playing music for 10 hours. By the time I listened to it again, all became normal.

ear wax?
blocked sinus?
mood change?

http://www.head-fi.org/forums/f4/sen...rrived-433059/

There's no crying in head-fi...

Ed,

It seems to me that the core of the disagreement here is in defining what constitutes "useful" evidence of burn-in (or lack thereof).

As a general matter, I think we can all agree that naked eye (or in this case, naked ear) observations constitute empirical evidence. For example: even absent a ruler, we should all be able to agree that an ipod mini is smaller than an ipod classic based solely on visual observation. But with respect to listening impressions and the burn in debate, certain questions remain: (1) is the evidence direct/indirect; (2) as qualitative data, is it trustworthy; and (3) what conclusions does the evidence entail (or merely, possibly support?).

I will also note that from a legal standpoint, such user testimony undoubtedly constitutes "competent evidence" in the sense that it is descriptive of the personal experience of the witness. Although indirect, I think it would clearly be "relevant" with respect to burn-in. Whether or not it is persuasive is a separate matter.

From the above quote, you seem to be indicating that you object to treating even a large sample of user impressions as scientific evidence, based on lack of controls, and I assume, the non-quantifiable nature of the data? Does this mean you reject the scientific value of all qualitative surveys - or do you simply disagree with the conclusion?

I think the truth of the matter is that there is some evidence (albeit indirect) on both sides - and there is just a sharp schism as to which evidence we tend to find convincing.

You have cited, as "relevant" evidence against burn-in, articles addressing the minimal measurable results of burning in certain speakers. The IE8 burn-in advocates (myself included) reject the value of your evidence because the articles did not test or address the IE8's specifically. (And I would imagine that you concede different transducers could conceivably change at different rates and/or magnitudes over time - although you would deny that these changes, however small, would have any real impact on sound quality.)

By contrast, the burn-in crowd believes that their observational evidence is relevant because they/I believe the perceived change in sound likely results from subtle changes in the hardware (rather than in perception of the hardware). Critical to this interpretation of the observational evidence is the fact that most of us who have listened to the IE8's disliked them out of the box, set them aside, and perceived change many hours later. (Akin to eating a familiar dish in a restaurant that tastes different on a subsequent visit.) For me at least, it seems hard to believe that we somehow adjusted to the sound on a subjective level despite the fact that we were not actually acclimating over any duration of time. Rather, the change was perceived after hours and hours of non-listening.

So it boils down to a simple judgment call. What is the logical presumption in light of the aforementioned imperfect evidence? Are we allowed to accept a philosophy whereby inductive arguments and indirect evidence have value resulting in an opinion on the matter? Or are we forced to adopt burn-in agnosticism until measurable results confirm or deny a theory?

Interesting. I like how Sennheiser has made certified frequency response graphs for each HD800. Overall, each frequency response graph looks pretty consistent with each other with small dBspl variations at certain frequencies. Now if they only made one for each IE8...

Personal attack noted.

And I never once claimed that people here are imagining things.

Because it is extremely difficult and expensive to do. And even if the actual sound output by each IEM was identical it wouldn't be once it reached your eardrums, because your ear canals are not identical.

The differences are easily measurable and of a magnitude that one would expect to be able to hear. On the other hand the results of "burn-in" (beyond a few seconds) are not measurable. Yet some here expect to hear that difference.


The unit to unit differences between any units in a production run are generally large enough to be quite audible on A/B audition. My own speakers are an example. The stereo image is excellent, but on pink noise each has it's own easily audible character.


It is only to be expected because people have been told in advance there is a difference and people (including me of course) are very suggestible. It is called "expectation bias".

All I can say to that is that there are so many misconceptions in it I don't have time to cover them all.