If paper-cone drivers change physically, why wouldn't they keep changing indefinitely? Are there any scientifuc papers about "how to engineer paper drivers so they change, but in desirable ways, and then magically stop changing after 30 hours".
-
WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!
Do Audio Speakers Break-in?
- Thread starter amirm
- Start date
^ it might change indefinitely or take 500 hours before it stops changing in any significant discernible way......then maybe we can conclude they aren't worth measuring or not even worth the investment ..
or could get gradually better then top out at 10 hours and go downhill from there...
You'll never know until this get tested with actual data to back it up ....
I assume ppl don't come to ASR just to have their opinion validated so they can stick to whatever they believe. They can go to any other forum for that.
or could get gradually better then top out at 10 hours and go downhill from there...
You'll never know until this get tested with actual data to back it up ....
I assume ppl don't come to ASR just to have their opinion validated so they can stick to whatever they believe. They can go to any other forum for that.
Don't want to give an opinion on break-in periods, sound changing, etc. basically because i have absolutely no idea.
But what i do know is that the sort of materials used to make speaker membranes might change over time and their mechanical properties as well. And this might happen whether you use them or not. Temperature, humidity, exposure to light or chemicals (i.e. cooking fumes if they are in the kitchen) or simply time (i.e. migration of plastizisers) can all contribute to aging of a polymeric material, mechanical stresses (=use in the case of a speaker membrane) can affect as well.
There is something else that applies to certain materials that is the "curing" process. These are typically chemical processes that take place during production, that for instance, make a material stiffer. Well, these processes might take very long, meaning that an article might get to the consumer before the curing is completely finished (don't know if this likely in the audio industry), i am talking about very very slight evolutions, as most of what is going to happen is going to take place in the first few minutes, but the process can indeed continue afterwards in some instances.
Note that this is a general comment that relates to polymeric materials in general, i Don't know much about how drivers producers choose their materials, and i trust they do a good job, but all polymeric matrials have a life period and all could change (even if only slightly) over time. Now, if all this can have any effect at all in sound, positive or negative, if the speaker is used properly, i have absolutely no idea. The message is that materials are not static over time.
But what i do know is that the sort of materials used to make speaker membranes might change over time and their mechanical properties as well. And this might happen whether you use them or not. Temperature, humidity, exposure to light or chemicals (i.e. cooking fumes if they are in the kitchen) or simply time (i.e. migration of plastizisers) can all contribute to aging of a polymeric material, mechanical stresses (=use in the case of a speaker membrane) can affect as well.
There is something else that applies to certain materials that is the "curing" process. These are typically chemical processes that take place during production, that for instance, make a material stiffer. Well, these processes might take very long, meaning that an article might get to the consumer before the curing is completely finished (don't know if this likely in the audio industry), i am talking about very very slight evolutions, as most of what is going to happen is going to take place in the first few minutes, but the process can indeed continue afterwards in some instances.
Note that this is a general comment that relates to polymeric materials in general, i Don't know much about how drivers producers choose their materials, and i trust they do a good job, but all polymeric matrials have a life period and all could change (even if only slightly) over time. Now, if all this can have any effect at all in sound, positive or negative, if the speaker is used properly, i have absolutely no idea. The message is that materials are not static over time.
I think there will be some very minor changes with use, but nothing significant as to perceivable. If a speaker can sound much better after say, 500 hrs of use, in it's lifetime which is a lot of 500 hours I would expect it will degrade more and sound like crap after say 10 years. which we all knows isn't the case.
DSJR
Major Contributor
I forgot where I read this, but going back many many decades to when Wharfedale were UK owned and made Wharfedale, it's said that a visitor to the factory was told the best sample of a particular model was the dust covered one up on a bracket or shelf used all day for radio or whatever for months/years on end... I can't speak for the larger models, but my late 60's Denton W20's have paper cones and rubbery surrounds and today, a 'nice but slightly foggy' tonality to them, perfect for the cheap groove grinders and low powered distortion boxes often used with them back then...
I do remember some top Sennheiser headphones baing tested out of the box and then after 48 hours of use (not sure of it was continuous music or test signals). The post 10kHz frequencies did change a dB or two upwards in level. This leads me to suspect that tweeters may need some hours of use to fully stabilise, even if it's shifting ferro-fluid around the coil better? Of course, twenty years plus on, said ferro-fluid is drying out and the tweeters will be noticeably different (possibly better as some were set too high when new)... Bass-mid units though, not sure unless they sag on their suspensions and go off centre (geriatric Spendors) or the surrounds go hard (middle aged Spendors!) needing brake fluid applications to soften them, if only for a short while...
I do remember some top Sennheiser headphones baing tested out of the box and then after 48 hours of use (not sure of it was continuous music or test signals). The post 10kHz frequencies did change a dB or two upwards in level. This leads me to suspect that tweeters may need some hours of use to fully stabilise, even if it's shifting ferro-fluid around the coil better? Of course, twenty years plus on, said ferro-fluid is drying out and the tweeters will be noticeably different (possibly better as some were set too high when new)... Bass-mid units though, not sure unless they sag on their suspensions and go off centre (geriatric Spendors) or the surrounds go hard (middle aged Spendors!) needing brake fluid applications to soften them, if only for a short while...
maybe that's the caps get charged or some stuck dirt on the motor get shaken off, I know that should have something keep on changing as in a car engine, but I can't imagine any significant change in the driver itself or so in a speaker's lifetime, especially you know that a lot of high end speakers are tested and measured individually before shipment, if it can change so drastically I don't think any factory calibration could result in something having great variation
There is certainly some truth in this.
To what extend, I have no idea.
One thing is sure, is that the vibration damping is one of the important properties a cone needs.
The fibre and pulp's modulus is influencing the sonic velocity and sound dissipation is also altered.
Therefore synthetic fibers like aramid, HmPe, carbon, PBO or ceramic and metal cones are being used.
Pulp (paper) cones can alter under humidity and heat conditions.
Again, no idea to what extend it will be significant in measurements though.
My hearing loss is now at the wrong end of moderate (fairly standard age related hearing loss) and a few months ago I finally bit the bullet and got fitted with hearing aids. It was an interesting object lesson in just how pliable and adaptable human hearing is. At first it was like hearing a very loud world through a tin can in an echo chamber, but within a couple of weeks things sounded fairly normal. I can still hear some of the digital crud, but that is about it - in a modern hearing aid you have a tiny AD\DA convertor doing a lot of dynamic range and frequency shifting, so it is understandable. Tube amps, yes, they need break in, but only a few hours (and you can measure that, a tubes electrical characteristics change over time and most of that change is in the first few hours). But anything else - no, it is your hearing adapting itself.
Audiophile myth un proved. The Thiele parameters changes with the time in the two sens. https://www.audioholics.com/loudspeaker-design/speaker-break-in-fact-or-fiction
What is fun with the burn in, is his reversibility.
https://forums.audioholics.com/forums/threads/speaker-burn-in.75614/
So audiophile when you listen your speakers you need to burn in before each listening.
Good luck audiophile.
My comments apply to any polymeric material including aramid and PBO fibers, but when fiber reinforced materials are used, normally aging affects much more and earlier the matrix material (PP nylon or whatever it is) than the fiber that tends to be more robust and are protected by the matrix, that is more exposed
Last edited:
Also true that ageing affects particularly advanced synthetic fibers of any kind when light exposed.
But the turn around is to be protected and enclosed in polymers and then the ageing is very minor..
All the above is fine - but explain why burn in always improves the sound. We never hear of break-in making a produce worse. Or of products reaching an end of life due to extended break-in like effects.
This isn't to say that there cannot be physical changes, but there seems to be an assertion of some form of magic property present that always improves the sound. That is a serious stretch.
This isn't to say that there cannot be physical changes, but there seems to be an assertion of some form of magic property present that always improves the sound. That is a serious stretch.
I wonder how many decades ago the burn-in theory originated... and why there is still no solid evidence measured.
One thing that does change during the break-in period is the neurons in the listeners brain. Maybe some form of auto-suggestion or priming explains the devout adherence to "I swear it sounds different". They truly perceive it as different, even though there remains no scientific objective measurement data whatsoever in 50 years, of any difference.
Aren't paper speakers becoming less common? Yet people still report break-in.
One thing that does change during the break-in period is the neurons in the listeners brain. Maybe some form of auto-suggestion or priming explains the devout adherence to "I swear it sounds different". They truly perceive it as different, even though there remains no scientific objective measurement data whatsoever in 50 years, of any difference.
Aren't paper speakers becoming less common? Yet people still report break-in.
Speaker burn-in is pretty silly. Now cables - well you better burn them in for at least 200 hours or you're just not getting near their true potential.
Even paper cones are usually treated with stiffeners, but as they break down with use I'd expect distortion to get worse as modes and breakdown become easier to generate due to the "softer" (less stiff) cone material.
But IME, the surround and spider are the largest causes of conventional speaker driver break in, not the cones. And that usually takes seconds to minutes to go past audibility. But, I am not a speaker designer, though this subject has been beat to death (well, I wish) and several folk on here and elsewhere who are speaker designers have commented that it is not a significant effect after the initial run-in.
But IME, the surround and spider are the largest causes of conventional speaker driver break in, not the cones. And that usually takes seconds to minutes to go past audibility. But, I am not a speaker designer, though this subject has been beat to death (well, I wish) and several folk on here and elsewhere who are speaker designers have commented that it is not a significant effect after the initial run-in.
Burn cable cryogenic?
You mean there are people listening without having the cables kleptogenically, sorry, cryogenically, treated first? How appalling, doesn't it make their ears bleed? One of the sillier misapplications of theory - yes, freezing a cable to very low temperatures will change it's crystalline structure and conductivity, but as soon as it warms up it will change back. And moving it in any way will also affect it - anyone here ever broken a solid core cable by bending it once to often? I have, more than once, that is why I hate working with solid core cables.
Similar threads
- Poll
