Speaker Break In: Fact or Fiction?

[Sheep]

The measurements I saw on there some time back were done by incompetant people whom were not ensuring a control situation. If you witnessed a test that did employ proper controls, I would appreciate a link to such. All I saw was normal variation of measured response due to not having controls set up. A seemingly trivial move of the headphone position by a 1/8" between two measurements will affect the measured response difference visibly in a graph.

-Chris

Listen to him, he has cans coming out the yang ying.

SheepStar

 

[JennAir]

You're all focusing on the possible mechanical changes that can occur to a driver after a number of hours playing but you're forgetting what effect that has on the electrical properties of said driver. If the suspension "loosens up" the electrical properties of the motor will also change in an inversely proportional manner. Therefore, the performance remains the same. Electrical properties also change when the voice coil heats up but revert back when the voice coil cools down.

 

[WmAx]

You're all focusing on the possible mechanical changes that can occur to a driver after a number of hours playing but you're forgetting what effect that has on the electrical properties of said driver. If the suspension "loosens up" the electrical properties of the motor will also change in an inversely proportional manner. Therefore, the performance remains the same.

The Fs(the only substantial change) of a woofer for example, lowers after break in and the change is *largely permament. The change is reflected in the electrical measurement of impedance, and the change affects the frequency response of the system. The change can not be and is not counter-acted by an inversely proportional reaction.

*The suspension, if stressed enough, may have temporary stress that can have some effect(s), but the majority of difference, related to Fs for example, comparing a never used driver to a used one will be permanent.

-Chris

 

[JennAir]

I see I phrased that badly.
The earlier posts in this thread, unless I missed something, were all about the mechanical effects of "break-in", however, a loudspeaker driver is an electro-mechanical device.
Yes, Fs is the lowest impedance peak in free air, and yes, when the mechanical compliance is less following "break-in" then Fs will be lower.
It is not the only substantial change to the electro-mechanical parameters of the driver following "break-in".
Vas is also related to mechanical compliance so when Fs lowers, Vas increases.
Net = 0.

 

[WmAx]

Vas is also related to mechanical compliance so when Fs lowers, Vas increases.
Net = 0.

The increase in Vas does not offset the effects in an equal inverse proportion to Fs reduction to create a zero sum difference.

But besides that, I am not sure what the big deal is, since it is doubtful it makes a difference of a magnitude that is audible(and the difference is even very subtle in a measured plot response) in a normal case. I have only discussed some effects from break in, I have not made any claims to the audibility of such.

-Chris

 

[JennAir]

it is doubtful it makes a difference of a magnitude that is audible(and the difference is even very subtle in a measured plot response) in a normal case.

Exactly. Qts will also lower because Qes drops as the suspension gets softer. The net result is that the F3 in a given box stays the same; the change is complimentary.

 

[pikers]

Yet I'm a stubborn bastard. I note that since I listen regularly to several different sound systems on a regular basis and still note subtle changes in most speaker systems during the first several hours of use, that there most definitely is a "break in" for those of us with an ear capable of hearing it.

Most likely it is your acoustic memory that is not as good as you think it is. Perhaps you should try a set of new speakers and compare it to the same model but used, behind acoustic curtins.


The rest of you can shake your heads & point to the indisputable measurements which are so minute that "no one could really be hearing that effect". If you really believe that, next time just by your speakers from a website based on "specs".

Unfortunate that you dismiss the science that brought you the audio equipment in the first place.

The science that brought the equipment has little to nothing to do with the perception of it.

Let's all try these elaborate double-blind tests, to increase the difficulty of percieveing what we already know, just to satisfy some guy on a website.

 

[pikers]

Tweeters weren't directly addressed b/c they experience even less break in than mids and woofers. 50hrs of usage is likely your ears getting used to the speakers rather than them improving in fidelity.

We aren't necessarily discussing an improvement. What we're discussing is the FACT that spiders and surrounds in a speaker assembly, like anything else that flexes repeatedly, will "loosen" and change properties.

Someone asked earlier why anyone would bother designing something that they knew would change properties over time. The answer is easy; the engineers predict this change, and in fact design speakers under the assumption that there will be a slight (typically better) change.

The fact that people ignore this basic fact is really mind boggling. Nothing pliable will maintain perfect response as in day one. Tires, jeans, rubber bands; nothing that moves repeatedly will maintain the same response characteristics.

 

[tlparker]

Other experts might disagree.. Peter Duminy

There has been a lot of talk lately about Speaker Break In among our forum users. Since there seems to be much confusion and misinformation about this topic we asked Mark Sanfilipo (our resident Loudspeaker Expert) to author an article on this topic and share his experiences and research.

Speaker Break In

who worked for a long time at B&W has commented on this before over at AVSforum. (His site is http://www.peterduminy.shim.net/). He did mention that there were different materials that affected burn-in time, at the time he was discussing burn-in time differences between B&W 703's and 704's (he actually preferred the latter after a couple hundred hours of burn-in). I'm not sure the tests here are quantitative enough to provide the definitive answer (if there is one).

 

[Screwman]

If there is actaully a change occuring to the speakers you would expect that there will be a fair number of instances where the sound of the system will degrade as the speakers break-in. This will be especially true when a system has been carefully built up using actual component measurements. but this is not the case.
It's interesting to note that when people talk about having their speakers 'break-in' with time they always speak of an improvment in the sound. If there is actaully some sort of a mechanical or physical change occurring then statistics will tell us that there is just as good a chance that the sound will be worse after break-in. Or is is only possible for speakers to improve but never degrade? To universally have an improvemnt in sound occur due to break -in is so far faetched as to be almost an impossible happening.
Break-in is in your ears, not in the box.

 

[Danny Richie]

It looks like the resident "expert" could use a lesson or too from the industry professionals.

Leap generated simulations are nothing but a mathematical calculation based on input figures. This in no way should be interpreted as actual measured data.

I posted some real measured data on speaker burn in here: http://www.gr-research.com/burnin.htm

I also have had lots of custom drivers built for my clients and for our own products by many well known driver manufacturers. Their data and conclusions regarding driver burn and time needed for burn in parallels my own.

No driver manufacturer that I know of would ever fall for the notion that a driver fully burns in within the first ten seconds and then maintains the same parameters from then on.

Danny Richie
GR Research

 

[j_garcia]

Thanks Danny, that's great info. So would you say that this burn in is dependent on the driver or is it fairly typical? I know electronic components need to burn in, in most cases, but how many hours realistically? I've seen manufacturers claim hundreds of hours.

 

[gene]

It looks like the resident "expert" could use a lesson or too from the industry professionals.

Leap generated simulations are nothing but a mathematical calculation based on input figures. This in no way should be interpreted as actual measured data.

I posted some real measured data on speaker burn in here: http://www.gr-research.com/burnin.htm

I also have had lots of custom drivers built for my clients and for our own products by many well known driver manufacturers. Their data and conclusions regarding driver burn and time needed for burn in parallels my own.

No driver manufacturer that I know of would ever fall for the notion that a driver fully burns in within the first ten seconds and then maintains the same parameters from then on.

Danny Richie
GR Research

Danny;

It's kinda hard to take anything you say seriously when you promote speaker cable break in. If one can't even get the basics of wire correctly, then everything else is left to chance.

http://www.gr-research.com/components/wire.htm

 

[j_garcia]

You still sell speaker wire? I thought you guys stopped shipping those.

 

[Nick250]

Danny;

It's kinda hard to take anything you say seriously when you promote speaker cable break in. If one can't even get the basics of wire correctly, then everything else is left to chance.

http://www.gr-research.com/components/wire.htm

Gene gets a TKO in the first round. Danny is quickly escorted from the ring for his own protection. The fans go wild. We now return to your regular programing.

 

[j_garcia]

No offense to Gene, but I trust Danny's numbers. Otherwise, I wouldn't have bought his speakers...my ears tell me he knows what he's talking about. Heat in the voice coil will definitely change, but I didn't think that change would be a lasting one. I don't doubt that a change would occur, but the question is, how does that vary depending on the size and design of the voice coil and/or suspension? Clearly the parameters of the test case changed, but what did that translate to in terms of the sound of the driver?

 

[Danny Richie]

So would you say that this burn in is dependent on the driver or is it fairly typical?

This is typical with any driver.

I know electronic components need to burn in, in most cases, but how many hours realistically?

It depends on the type of components used in the electronics. Some caps for instance will need 50 to 100 hours while a Teflon based composite cap like the Sonicap Platinum will require 500 to 1000 hours.

It's kinda hard to take anything you say seriously when you promote speaker cable break in. If one can't even get the basics of wire correctly, then everything else is left to chance.

That's brilliant. So you conclude that my measured data must be all wrong because I witness something that you either don't understand or have never witnessed yourself.

I guess next you'll tell me that capacitors don't burn in either, or that all power cords are the same, etc.

Maybe you should also spend some time discussing these issues with industry professionals. I don't mean those that sell wire either. I am referring to those that manufacture wire.

Maybe you know of a guy that will state for you that the dielectric constant of the coating of the wire will stabilize in the first ten seconds. That would make sense right?

You still sell speaker wire? I thought you guys stopped shipping those.

I don't have time to make it any more that's for sure. I have sold a few guys the wire and ends so that they could do all the braiding themselves. I mainly only offered it so that my customers could get a good set of wires at a budget wire price.

Clearly the parameters of the test case changed, but what did that translate to in terms of the sound of the driver?

Maybe you can answer that question for yourself. You've built a pair of our speakers. I know it may not be a night and day deal for you if you listened to them all during the burn in process, but it is sometimes very noticeable.

It would be more apparent if you compared your pair to a fresh pair.

People notice the burn in effects all the time, and these guys just use their ears: http://av123forum.com/showthread.php?s=&threadid=13912

 

[j_garcia]

The main pair I bought came from Brian at RAD, but I did do the Sonicap upgrade on them as well as the GR-T2 tweeters, and the difference was very noticable. I can't honestly say I heard the difference as they broke in though (as you said, I was listening to them basically every day), all I can say is they still sound wonderful

 

[gene]

That's brilliant. So you conclude that my measured data must be all wrong because I witness something that you either don't understand or have never witnessed yourself.

Measured data on what, speaker cable break in? Hmm since I have over 100k worth of test gear to measure cables, along with a fairly decent EE background with a BSEE, I think I have a basic understanding of electrical theory and it applies to cables.

Perhaps you should do a little reading yourself:

Audio Cable Break In: Science or Psychological?

I guess next you'll tell me that capacitors don't burn in either, or that all power cords are the same, etc.

Why are you attempting to compare capacitors with a passive element such as wire? This is the typical straw man argument used by cable snake oil vendors. Surely you have more common sense than that to differentiate the difference between the two? I know, don't call you Surely

As for power cords. No they are NOT all the same. Some esoterics are really poorly designed and DON'T even have UL approval. As for their sound, only poorly designed power cords are sonically distinguisable on poorly designed esoteric gear.

Maybe you should also spend some time discussing these issues with industry professionals. I don't mean those that sell wire either. I am referring to those that manufacture wire.

Actually I do. Does the name Steve Lampton from Belden ring a bell? Perhaps you aren't aware of many of the co-authored articles we did for several pro print publications like Pro AV. I don't want to put words in his mouth, but he and I are pretty much on the same page just like every other credible electrical engineer when it comes to cables.

As for other industry professionals, how about Henry Ott and Dr. Howard Johnson?

Perhaps you should check out some of our cable articles that they contributed to and also peer reviewed.

Audioholics Cable Articles

Maybe you know of a guy that will state for you that the dielectric constant of the coating of the wire will stabilize in the first ten seconds. That would make sense right?

Well I know of some companies that slap batteries on their dielectric to supposidly stabalize the dielectric. LOL good show

Perhaps you should check our our cable solution. We spank those electrons that misbehave

Audioholics GLOB

I'd also encourage you to read an article I authored on Cable Dielectrics:

Dielectric Absorption in Cables

 

[Danny Richie]

Measured data on what, speaker cable break in?

Ah, you questioned the validity of my measured data on the M-130 woofer because I recommended a break in period for our speaker cables.

Hmm since I have over 100k worth of test gear to measure cables, along with a fairly decent EE background with a BSEE, I think I have a basic understanding of electrical theory and it applies to cables.

Yet, you can not discern audible changes of before and after burn in of a set of cables? Interesting... It makes me wonder what audio gear you use.

Audio Cable Break In: Science or Psychological?

I read it. I didn't see any science though. Just a typical opinion.

I mentioned capacitors and power cords not to make any arguments but to get a better feel for the range of your beliefs. Looking over your site now I am beginning to get a good idea.

I could also site you just as many cable manufacturers that clearly state that cables do require a burn in period, probably even more. I had dinner with one at the CES a few years back. He was a metallurgist for the US government prior to manufacturing high end audio cables. I believe he now holds several cable patents.

Audioholics Cable Articles

That reminds me of Peter Aczel's 10 biggest lies in audio list. Humorous, but little facts to be found, and more dis-information than information.