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Do driver in headphone degrade when age? - Page 3

post #31 of 54
Quote:
Originally Posted by Uncle Erik View Post

The problem with "burn in" is that if a product genuinely changes, it opens up a lot of liability for the manufacturer.

If a headphone has a one-year warranty, then someone could claim that the product is defective because it changed and make a warranty claim.

Management, legal and accounting would be all over engineering if products were actually changing with use. Further, products are tested for thousands of hours before they go on the market. Management reviews the tests. If a major change occurred, they'd make engineering fix it.

Even if they found that X number of hours were necessary for a particular design, they'd burn them in at the factory, just to make sure it didn't change further and potentially incur warranty costs.

Burn in is magical thinking. People love to think they're doing something special that makes their experience unique.

If you really want to do something that changes your listening experience and learn more, go get a soldering iron and build a CMoy. You'll actually learn something instead of performing an audiophile folk ritual. After the CMoy, apply what you learn to building amps, DACs, or any number of cool projects. Those will improve your listening experience. A ceremony won't.


The thing is that the change isn't heard by the naked ear when people just listen to the headphones for enjoyment.  It's not something that you listen for if you don't know it's there (many consumers don't even know about this).  They won't hear it unless you listen for it.

 

Also, there has to be a reason why so many people are hearing this?  You can't just say they are all magically thinking or eating placebos, it just doesn't work that way.  If a huge group of people experience a phenomenon, then there has to be some truth behind it, especially when more than one person report back with similar results, if not the same.  Look in the HF5 thread (in praise of HF5) to see another person with similar results. 

 

There is no doubt that sound changes in headphones, it's been tested with equipment, CNet did an article on it with frequency response curves from another source (they used Grados to test with).  Note that a small change in dB is actually a big change sonically since dB is listed in a logrithmic graph when the actual pressure level is linearly measured.  So a 20dB drop from 20 to 0 does not equal a 20dB drop from 80 to 60.  Math as follows:

 

dB to sound pressure:

20dB = 10^2 Pa; 0 dB = 10^0 Pa = 1;  100 - 1 = 99 Pa change

80dB = 10^8 Pa; 60 dB = 10^6 Pa; 10^8 - 10^6 = 99000000 Pa = 99000 kPa

 

The change is huge in comparison. 

 

As long as it is measured the same way both times, and they show change, we know it exists. 

 

Now we have to figure out why it exists, and why there are conflicting results for it.  Saying that burn-in is a magical thinking or an audiophile folk ritual doesn't say anything without facts to back it up.  Just because you didn't hear it, doesn't mean you can put down the people who did.  You have to come up with a logical reason why these people are coming up with the same exact results (or even any results).  You can't deny data that a person observed, you can only say it isn't true with other facts/reasoning for why it might have happened.

 

For example, one reason a person might not hear or notice burn in is because the change in change of sound (sounds weird, mathematically speaking it'd be dC where C = change in sound @certain frequency) is small and not detectable.  Different ears hear differently.  This is just one reason, there may be others.  This does not mean that it is happening to you. 

 

All I'm saying is that there has to be a reason why people are hearing things the way they are, we have two distinct groups, and there has to be a reason why both hear these changes (or lack thereof) the way they do.  Placebo is not an answer for either since the number hearing it are too large.  Neither are magical fairy tales.

 

post #32 of 54
ok so im fairly new, but with the 3 pairs of headphones ive had, 2 i noticed burn in. The AKG K518 Dj and Sennheiser HD238. Im a burn in believer. I tested out of box, after a few hours, a so on. And there was change. The main change i noticed was in the bass, on the HD238 the bass distorted alot at first, but then it smoothed out. And the AKG's got an overall smoother sound.
post #33 of 54
Quote:

Originally Posted by tinyman392 View Post

If they did measurements in dB, then a small change in dB is extremely large.  Starting from zero, every ten decibels you gain is 10^x the energy (the SI measurement for loudness).  For example:

...

I do want to see if their data shows that a driver can actually fail due to overuse (normal use), it would show up in their data for sure :)

Uhm, we're talking +/- 0.25 dB maybe. That's well below the threshold of audibility, which for trained listener is close to 1 dB in a certain frequency and loudness range. Heck, fit variability is higher than the mythical burn-in I haven't been able to detect. (up to 2 dB here and there with the same fitment, this is audible.)


Edited by AstralStorm - 7/11/11 at 1:03pm
post #34 of 54
Quote:
Originally Posted by AstralStorm View Post

Uhm, we're talking +/- 0.25 dB maybe. That's well below the threshold of audibility, which for trained listener is close to 1 dB in a certain frequency and loudness range. Heck, fit variability is higher than the mythical burn-in I haven't been able to detect. (up to 2 dB here and there with the same fitment, this is audible.)



+/- .25 dB is doesn't mean anything since it can mean 20Pa change or even a 3000Pa change (which is more than audible), even further, it can also mean a 300000Pa change.

 

By the way, the threashold for audiblility is 0dB...  We can hear anything above 0dB.  That's how the system was set up.


Edited by tinyman392 - 7/11/11 at 1:10pm
post #35 of 54

0 dB SPL RMS = reference pressure is defined as 20 uPa (micropascals) in air, at the eardrum, normal pressure and temperature, at 1 kHz. (as per ANSI)

Wikipedia says it's about the pressure caused by a sound wave emitted by a mosquito at 3m. Pretty quiet. 1 Pa is roughly 94 dB SPL RMS. Wikipedia has some "loud traffic" there as an example, but I'd describe it as the jackhammer at 6m. Painfully loud.

 

However, sensitivity is not resolution. Ear/mind is less resolving with regards to the difference in volume - as described by various double blind listening tests you no doubt can find using EBU AES as keyword. Logarithmic scale actually keeps the "loundess resolution" close to constant pretty well, so the real threshold for difference in clear tones is between 1 to 3 dB. (Edit: no, it doesn't depend on frequency, see below.)

It's worst at the extremes, slightly related to absolute sensitivity at that frequency.

(Edit: It's not actually logarithmic, but pretty close: https://secure.wikimedia.org/wikipedia/en/wiki/Weber%E2%80%93Fechner_law#The_case_of_sound )


Edited by AstralStorm - 7/11/11 at 5:41pm
post #36 of 54

Direct conversions of dB to Pa, and yes, it goes up fast:

 

  • 0dB = 10^0 Pa = 1Pa (no increase)
  • 10dB = 10^1 Pa = 10Pa (Increase of 9)
  • 20dB = 10^2 Pa = 100Pa (Increase of 90)
  • 30dB = 10^3 Pa = 1000Pa (Increase of 900)
  • 40dB = 10^4 Pa = 10000Pa (Increase of 9000)
  • 50dB = 10^5 Pa = 100000Pa (Increase of 90000)
  • 60dB = 10^6 Pa = 1000000Pa (Increase of 900000)
  • 70dB = 10^7 Pa = 10000000Pa (Increase of 9000000)
  • Continue

So lets say the sound went from 70dB (measured @ certain frequency) to 69dB (measured at the same frequency) then you'd get (in Pa) 10000000Pa - 7943282.347Pa = 2056717.653Pa change.  Converting that 2056717 back into dB you'd get > 50dB change in sound...  Is that audible?  I'd hope so.  Remember, dB vs Pa isn't linear, they go up in powers of 10.  Notice that this was to calculate a 1dB drop in intensity (70 to 69), but the result was actually a 50dB change in total intensity due to the way the dB system is set up.  And most of the time, the change goes from much larger numbers like 90dB to 89dB which would yield a total of about 80dB of intensity change.  In order to do these calculations you have to convert dB to Pa.

 

Conversion below:

10^(dB/10) dB = Pa

 

Notice how this is not even close to linear.  It is logarithmic, 10^power is the reason behind this.  The intensity change is huge, even though it seems small.  dB graphs can be misleading due to the scale of the vertical axis.

post #37 of 54
Quote:
Originally Posted by tinyman392 View Post

Direct conversions of dB to Pa, and yes, it goes up fast:

<BS here>

Notice how this is not even close to linear.  It is logarithmic, 10^power is the reason behind this.  The intensity change is huge, even though it seems small.  dB graphs can be misleading due to the scale of the vertical axis.


Again. 0 dB SPL is 20 uPa which is 2 * 10^-5 Pa. And you calculate the next step as x dB SPL RMS = 20 * log10(p/pref) where the reference level is constant and well defined. (non-RMS uses 10 * log10(p/pref) due to no squaring of the pressures.)

Indeed it's not linear, however our volume discrimination capability is not linear either. (it's not logarithmic, but it's close) See the link I've posted.

So the decibel change in volume would be perceived pretty much the same in a large range of volumes. The logarithmic approximation breaks down at high pressures, which are not recommended for listening anyway.

 

Note it's Decibels Sound Pressure Level not just "some decibels". Many people here would abbreviate that to just dB.

That's in contrast to dB power handling (with the base unit of in Watts), which is the more rarely used unit.

 

Edit: in dB SPL, 6 dB is almost exactly equivalent to doubling (2x, not 10x) the pressure in Pa.


Edited by AstralStorm - 7/12/11 at 2:57am
post #38 of 54

I read through your link...  I nice one too since you obviously skipped through the first sentence. 

 

Quote:
Weber's law does not quite hold for loudness

 

Now if you read an article about SOUND PRESSURE LEVEL, you'll notice that the first sentence says it's logarithmic.  Heck, there's a log symbol in the equation you supplied!

 

Also, notice that I did make a mistake in my calculations, they were off by a multiple of ten, however, the calculations aren't off since I converted back to dB using the same system (which cancelled out the multiples of 10)...  I rechecked my work using the equations on that wikiarticle I found...  The answers didn't vary much (a few decibel places...  Woo!).  Even further, I rechecked my work with this converter and everything checked out OK again.

 

A drop from 80dB to 79dB = .2Pa - .178Pa = .0217Pa = 60dB difference.  Again, using nice algebraic skills and converting back and forth.  Let's go back to the 70 to 69 I had earlier: 70dB - 69dB = .0632Pa - .05636Pa - .006832Pa = 50dB difference.  Again, in order to subtract decibels you have to first convert into something LINEAR, subtract, then convert back to dB.  As you can see, the difference is 10-fold. 

 

Equations used:

 

L = 20 log(Pmeasured/Preference) dB

Pmeasured = 10^(L/20)*Preference

 

L is the measured SPL in dB, Pmeasured is the measured pressure in Pa, Preference = 0dB (standard) = 2^-5 Pa

 

The first equation is given by Wikipedia, the second is algebraic manipulation, 100% legal. 

 

Don't give me some random BS about how sound pressure is not logarithmic when my physics book, physics teacher, and wiki-article state they are.  Also, read your articles entirely before you post them, that first sentence really gave me a good LOL :p  With that said, a 80dB to 79dB drop is 60dB difference while a 70dB to 69dB drop is a 50dB difference (the latter was shown above too).  Even when I use W/m^2 (even though it's rarely used), the answer won't change due to the fact that I'm converting back and forth from dB.  The final unit won't change, and it's a direct conversion.


Edited by tinyman392 - 7/12/11 at 7:50am
post #39 of 54
Quote:
Originally Posted by tinyman392 View Post
A drop from 80dB to 79dB = .2Pa - .178Pa = .0217Pa = 60dB difference.  Again, using nice algebraic skills and converting back and forth.  Let's go back to the 70 to 69 I had earlier: 70dB - 69dB = .0632Pa - .05636Pa - .006832Pa = 50dB difference.  Again, in order to subtract decibels you have to first convert into something LINEAR, subtract, then convert back to dB.  As you can see, the difference is 10-fold.

I'm not trying to specify dB SPL difference in terms of dB SPL - that's not useful.

So, it's (x+6) dB SPL and not x dB SPL + 6 dB SPL.

That's what everyone except mathematicians means by +6 dB. It's a different operator.

 

This is not constant pressure difference, however the difference in loudness is pretty similar to the ear, thanks to Weber-Fechner law (it's just an approximation)

https://secure.wikimedia.org/wikipedia/en/wiki/Weber%E2%80%93Fechner_law#The_case_of_sound

 


Edited by AstralStorm - 7/12/11 at 12:20pm
post #40 of 54

The law you keep referencing doesn't hold true for loudness (which is what the frequency graphs..  well graph out).  It's the first sentence in the article.  The loudness is measure through pressure, which is what the decibel system is derived from.  Loudness is measured in dB, and that's what I'm trying to show, a small change in dB from equipment that measures it is not as small as it seems.  You made .25dB seem like it was a really small change, and in some cases it is, however, in others. The change is quite large (as shown above numerous times).  You can't just add dB since they are in a logarithmic scale.  You have to convert it to a linear form first, then add, then convert back to the dB system.  Adding 6dB to something that's already at 90dB won't make a difference.  However, dropping from 90dB to 84dB is a huge drop.  That is what I'm trying to say.  And that drop can be heard regardless of what frequency range we are talking about (so long as it's within the person's hearing range).  If you get a small drop like this, the change is audible, and it will change the signature of the headphones. 

 

When looking at change on a frequency graph, the change in sound is not (x+y) dB, it's xdB + ydB.  Why?  The graph is set up that way.  In a scientific world, you can't add stuff that isn't in a linear scale, you have to make it linear first so you can add it (and that's what these graphs show, it's scientific).  IE, 90dB + 80dB != (80+90)dB (if it did, we would have blown our brains out by now with all the sound that happens on a daily basis).  It's not as simple as that.  Adding things that aren't on a linear scale is the equivalent of adding apples and oranges.  And don't tell me there are two addition operators, it doesn't work that way, ever. 

post #41 of 54

tinyman392, your math concerning sound pressure level expressed in decibels is mostly correct, but your incorrect understanding of perceived loudness - not absolute loudness in terms of pressure - is leading you to make a huge error in your conclusion.

 

Absolute loudness in terms of pressure is linear - yes, we know that.  It is by definition - the unit is force per unit area.  If the force doubles, the pressure doubles.

 

The reason the decibel scale is logarithmic by base ten is that it provides a convenient scale for representing the exponential range of sound pressure levels we experience in daily life, and it also happens to work very well with our ears' perception of loudness.

 

In your example, where you go from 80 dB to 79 dB - a 1 dB drop - you're saying that that is a 60 (73ish, actually) dB difference.  No, it's not!  It's a 1 dB difference!  You are dropping in relative value by 1 dB.  You are removing a 73 dB source of sound.  The overall SPL isn't dropping by 73 dB - you're just removing a source of that absolute quantity in Pa - but because at 80 dB that is only a fraction of the total sound pressure level, the decrease is only 1 dB of the total - remember, 3 dB is a doubling of pressure and 10 dB is a tenfold increase in pressure.  Obviously, if you remove a 73 dB source from a 74 dB overall level, you're going to have a larger decrease in the overall level as expressed in dB (it would decrease to 67 dB) because proportionally you removed a much larger part of the sound pressure level in Pascals.  The decrease in absolute sound pressure level in Pascals is the same in both cases, but the difference is that the decibel scale is relative, so it's not an equivalent decrease as a proportion of the initial value.

 

 

 

 

The thing you're sorely missing is that our hearing is also exponential in sensitivity.  Our ears don't care what the absolute, linear difference in sound pressure level is (until you get to very high SPLs where the eardrum tightens up to protect itself).  It is only the relative difference that matters within our ears' normal range.

 

For example, if you are listening to a recording and some detail is 3 dB down from the reference level, it remains 3 dB down no matter how loud you actually reproduce the recording.  The difference in absolute pressure changes, but the relative level compared to the reference level never does.

 

More specifically, we perceive sound so that a 10 dB increase - a factor of ten in terms of sound pressure - results in roughly a doubling of perceived loudness.  It doesn't matter whether you start at 0 dB or 100 dB, a 10 dB increase results in a doubling of perceived loudness.  The increase in perceived loudness can be calculated as follows:

 

Lp = 2^(1/10)^(delta dB)

 

Where "Lp" is the perceived loudness, with "1" being the base level at 0 dB of change; and "delta dB" is the change in decibels.  Note that "2^(1/10)" is the 10th root of 2.  It doesn't matter what the absolute difference in Pascals is between two levels - for perceived loudness within our normal hearing range only the ratio does.

 

So say, your decibelmeter reads 70 dB (average), and you turn up the music until it reaches 95 dB.  So, Lp = 2^(1/10)^(25) = perceived as 5.66 times louder.

 

Or, say some detail is at 42 dB below the average level.  Lp = 2^(1/10)^(-42) = 0.0544 = perceived as 1/18.4 as loud as the average volume overall.

 

You could make this absolute if you set the "perceived loudness" of 1 as being at 0 dB - you get a chart like this with perceived loudness at each decibel level:

 

Perceived Loudness                dB              Absolute SPL in Pa

 

1                                           0                20 µPa

2                                           10              200 µPa

4                                           20              2 mPa

8                                           30              20 mPa

16                                         40              200 mPa

32                                         50              2 Pa

64                                         60              20 Pa

128                                       70              200 Pa

256                                       80              2 kPa

512                                       90              20 kPa

1024                                     100            200 kPa

2048                                     110            2 MPa

4096                                     120            20 MPa

8192                                     130            200 MPa

etc., etc...

 

Finally, with our perceived loudness scale we have a scale where a linear increase means a linear increase in perceived volume.  We don't have that with our decibel scale, nor do we have that with the absolute sound pressure level in Pascals.   It's just more handy to stick with the decibel scale since it's such an easy format to play with mathematically, and it's still relatively easy to interpret in terms of perceived loudness.

 

For reference, the perceived loudness can be expressed in terms of the absolute SPL in Pascals.  Here's the equation:

 

Lp = 25.97*P^0.3

 

Where P is the pressure in Pa.  I was too lazy to derive the equation so it's just power regression fit curve, not the exact values.


Edited by BlackbeardBen - 7/12/11 at 6:01pm
post #42 of 54

Quit it with all the SOUND SCIENCE!!!!!

 

I had a pair of sony MDR-CD2000's they got better and better until about 5k hours when the right driver started rattling on curtain bass freqs.

post #43 of 54
Quote:
Originally Posted by BattleBrat View Post

Quit it with all the SOUND SCIENCE!!!!!

 

I had a pair of sony MDR-CD2000's they got better and better until about 5k hours when the right driver started rattling on curtain bass freqs.


NEVER!  LOL.  The rattling might not be burn-in/damage due to driver failure (from overuse).  I think a cable or two might be loose... :p

 

Back to science. 

 

@BlackbeardBen (cool username by the way :p)  I actually understand what you are saying, and do trust it (I've heard this somewhere, can't remember where).  Is there a name for this perceived loudness rule (I'm just curious).

 

Also, I did do some further digging in and did find some graphs of burn in: one chinese one (unknown time of burnin) that showed about a ~2-3dB change in the mids.  Doing the math with the equations you supplied: that comes out to a 15-23% (115-123%) increase in perceived sound (I have no idea what the units for this are :p).  I do believe this would be audible, really audible as well.  The graphs can be found here: http://www.head-fi.org/forum/thread/556732/partial-proof-that-iem-burn-in-works-yes-scientific-frequency-response-charts-included.  Look at the mids, the change is pretty big.

 

The second set of graphs, which seem a little more reliable show little to no change in the mids, however, the bass and highs (especially the highs) showed some change.  The change in the lows were miniscule at best (.5-.75dB change @ most), which is only 3-5% change.  I do not believe this would be audible unless you were blowing out your ears (then your ears close up to avoid damage, so it wouldn't be audible).  The treble is what I found to be the most change (which should be audible): These changes that varied anywhere from -3.5dB to -1.5 (also some .75, etc; but these aren't a big change as shown above already).  This change would result in a 10-21% loss in sound (which is audible) along with that some parts of this spectral area had increases anywhere from 1.5dB to 3.5dB which would result in a 11-27% change in sound which too is audible.  The graphs can be found here: http://www.innerfidelity.com/content/evidence-headphone-break-page-2 (I used figure for for the treble, and multiple graphs for the bass change.  I didn't do the mids as there was no more than .25dB change anywhere (which can't be detected; I'll admit to that now :p)

 

Please not when I say the change varied anywhere from x to y, these are the change in dB (delta dB; I'd say ddB, but that's just confusing).  So if either of these graphs are accurate enough, they do contain sound changes that are audible to the human ear (at least I'd assume a 10% change in sound would be audible; otherwise, 20% has to be).

 

I do appreciate the small corrections you gave me and the clarifications, if any of my numbers are off, please let me know.

 

post #44 of 54
Quote:
Originally Posted by tinyman392 View Post

 

NEVER!  LOL.  The rattling might not be burn-in/damage due to driver failure (from overuse).  I think a cable or two might be loose... :p

 

Back to science. 

 

@BlackbeardBen (cool username by the way :p)  I actually understand what you are saying, and do trust it (I've heard this somewhere, can't remember where).  Is there a name for this perceived loudness rule (I'm just curious).

 

Also, I did do some further digging in and did find some graphs of burn in: one chinese one (unknown time of burnin) that showed about a ~2-3dB change in the mids.  Doing the math with the equations you supplied: that comes out to a 15-23% (115-123%) increase in perceived sound (I have no idea what the units for this are :p).  I do believe this would be audible, really audible as well.  The graphs can be found here: http://www.head-fi.org/forum/thread/556732/partial-proof-that-iem-burn-in-works-yes-scientific-frequency-response-charts-included.  Look at the mids, the change is pretty big.

 

The second set of graphs, which seem a little more reliable show little to no change in the mids, however, the bass and highs (especially the highs) showed some change.  The change in the lows were miniscule at best (.5-.75dB change @ most), which is only 3-5% change.  I do not believe this would be audible unless you were blowing out your ears (then your ears close up to avoid damage, so it wouldn't be audible).  The treble is what I found to be the most change (which should be audible): These changes that varied anywhere from -3.5dB to -1.5 (also some .75, etc; but these aren't a big change as shown above already).  This change would result in a 10-21% loss in sound (which is audible) along with that some parts of this spectral area had increases anywhere from 1.5dB to 3.5dB which would result in a 11-27% change in sound which too is audible.  The graphs can be found here: http://www.innerfidelity.com/content/evidence-headphone-break-page-2 (I used figure for for the treble, and multiple graphs for the bass change.  I didn't do the mids as there was no more than .25dB change anywhere (which can't be detected; I'll admit to that now :p)

 

Please not when I say the change varied anywhere from x to y, these are the change in dB (delta dB; I'd say ddB, but that's just confusing).  So if either of these graphs are accurate enough, they do contain sound changes that are audible to the human ear (at least I'd assume a 10% change in sound would be audible; otherwise, 20% has to be).

 

I do appreciate the small corrections you gave me and the clarifications, if any of my numbers are off, please let me know.

 


Thanks!  I'm 24 and I've had a full beard since I was able to grow one at about 16, so when I was trying to figure out usernames for websites I thought of it...  It's catchy and unique (Well, except for an actual Blackbeard pirate reenactor named Ben!), so it fit perfectly for my website as well.

 

 

 

You might find this site interesting: http://www.audiocheck.net/blindtests_index.php

 

It should give you a feel for how different decibel levels are.  3 dB is a noticeable difference.  1 dB is very small but still easy to hear.  0.5 dB is even smaller and for some people is the limit of audibility.  I've been able to pass the blind test of the 0.2 dB difference but it's hard and takes a lot of concentration.  0.1 dB is very difficult and it's down to almost a hunch - the only time I tried I got the first 8 all right and then rushed to finish the last two because I had listener fatigue and may have started getting a little cocky, getting them both wrong...  If I really cared I'd continue taking that test to see if I really can tell the difference or not (of course I'd like to think I can), but it's boring and it doesn't add to my listening enjoyment.


It does however give you perspective in terms of perceived loudness differences.  A 2-3 dB increase from burn-in is a small but noticeable change, and a 1 dB difference is small enough that you might not necessarily notice it in actual music (but you certainly could with a half-decently run test).  There's just no huge changes that some people claim - at least none have been measured.

 

On top of all this, we need to know more about the test procedures for those tests - for any of them, any movement of the headphones in relation to the dummy heads is going to cause a change in the measurement that may be enough to cause a false positive or confuse the results.  The same goes for ensuring an identical seal with IEMs, and for pad wear on circum- and supra-aural headphones.  Until that is isolated, we have no idea whether any measured burn-in is a result of driver burn-in, pad burn-in, repositioning of measured headphones (which hopefully isn't a problem in a well-conducted test), or any combination of them.

 

This is one of the reasons I'm entirely skeptical of the veil/no veil claims regarding new/old Sennheiser HD 600 and HD 650 headphones.  I think it may just be a pad-wear issue - that seems far more likely to me given Sennheiser's claim that there is no difference.  If there was a positive improvement on an already well-regarded product, any intelligent business like Sennheiser would have made sure that everyone knew they were "improved", even if they kept the same SKUs.  I'm not saying it's impossible, just that there's no evidence beyond a few anecdotal reviews.

 

If you want to get more into burn-in there's a whole thread about it over in Sound-Science.  Pretty much all the arguments have been covered and covered again there.  Really, we need more evidence more than anything else.  I just wanted to clear up the whole perceived loudness thing here, because it was clear there were some unintentional misunderstandings.


Edited by BlackbeardBen - 7/12/11 at 11:04pm
post #45 of 54

OK, thanks for clearing it up though.

 

And I do agree there needs to be more evidence with this...  I myself had heard differences, they are small differences, but many small ones (which eventually add up).  I wish I could show some numbers, but I can't (change is relative to the listener, even perceived sound change is relative in a sense).

 

PS: that's a cool story behind your usename. 

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