Speaker Break In: Fact or Fiction?

[Audioholics]

It makes me wonder what audio gear you use.

It's certainly not a mystery. Equipment List

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.

Yes and I bet his wife could hear the difference in cables from the kitchen. It's going to be hard for you to poo-poo an analysis from Belden.

Differences in opinion are fine, but when you are talking to someone who has tens of peer-reviewed pages on the subject, please do your research first and address the specific issues you have with our research, measurements or conclusions.

Simply insinuating that "we must be idiots because you have tons of friends (who profit from the industry) that agree with you" is plain silly.

 

[Danny Richie]

It's certainly not a mystery. Equipment List

Oh no, you misunderstand what I am asking. I wasn't asking about measuring equipment. I am asking about audio equipment. What you guys listen with? What are your listening rooms like? You do post subjective analysis of audio gear do you not?

Anyone can measure LCR and write down the figures. Anyone can test a big group of cables and measure the LCR and say these are the figures. It is hard to refute the figures, and no reason to, but what do they mean?

I measured an M-130 woofer and the measurements clearly show change in compliance due to break in. Anyone else that runs the same set of measurements on a different woofer is going to get similar results and have. For those of us that do this for a living, it is common knowledge.

There is no questioning those results, but your site here fails to even properly conduct such test and conclusions have been drawn based on assumptions.

Now whether or not you can hear the difference or if you can hear the difference in wire, etc is for you to decide on your own. I can't tell you or anyone else what to hear. That is not what this is about. But likewise, you can't tell others what they don't hear either.

 

[Sleestack]

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

Despite the back and forth on the subsequent cable issue, I'm a bit surprised by this response from Gene. Why not address his comment directly initially rather than make this snide, unprofessional comment? It just sidetracked the topic for no reason. I suppose DR is member of the trade and is fair game, but addressing the topic is much more constructive than acting like every other immature (including me) member of this board.

 

[Audioholics]

We have already addressed the topic to death. We have numerous peer-reviewed articles on the subject that have been dismissed out of hand. It's like telling Steve Jobs he should really stick to topic and defend his knowledge of operating systems. I count three relevant links posted above by Gene (plus one comical one), and anyone who thinks a piece of wire needs to break in does not, frankly, deserve the time of day.

We have limited time and this kind of stuff is only relevant for profit-making.

If speakers break in, don't they also break-down? Does the frequency response not continue to change over time? How quickly? If not, why would it suddenly stop? Where are those measurements? Why aren't manufacturers selling extended warranties and opening up shops for replacing drivers after a period of time to keep the speakers within spec?

Oh no, I think I just started another money-making scam.

 

[gene]

Ok let's get back to the topic of speaker break in and put the cable snake oil debacle on hold for now. I just pinged a reliable industry source who does some of the most definitive research in loudspeakers on this very topic and here is what they had to say:

I just checked the forum and, as you say, the discussion got silly. Power cords too, my oh my. We all breathlessly await definitive technical measurements - but no, those are not necessary if someone reports hearing something. How naïve of me.

As for the loudspeaker measurements, our guys have lots of experience doing the same kind of stuff. It was pointed out that despite the mention that he "heated up the coil" he apparently didn't remeasure DCR while hot as he reports it as being the same in all measurements. Vas and Qts are synthetic quantities so we tend look at Mass and BL which should not change. Clearly his data are noisy as mass and BL did change.

The change in FS he reports and some level of recovery is real. We often see FS moving around a bit depending on temperature and break in. Surround material and design makes a huge difference. Some materials and designs are very stable.

Hot voice coils heat the air in the enclosure, thus heating the cone and surround and changing their mechanical properties - temporarily for the most part, but with the witches brew of materials used in paper cones, it is conceivable that there are instances where some of it could be permanent. For other cone materials, the effects are temporary (existing only while the material is hot), if they exist at all; which is why we look for cone materials that maintain similar mechanical properties over a wide temperature range.

Measured changes in LF output as a result of all of this tends to be of the order of 0.5 dB around 50Hz. As I said, in a room this has to be close to or below the threshold of audibility, but since competent designs account for it, it is not an issue.

Time to move on . . .

So it appears to me that if you have a poorly designed paper cone then the extent of break in will be more pronounced and varying. Personally I prefer using a more consistent design that maintains its performance characteristics throughout the life cycle of the product

 

[nibhaz]

Between the lines answer: the audible effects of break in may only arise if the physical driver is of poor design, or the speaker system as a whole was designed poorly...yes, no?

What does that say about the systems of those who claim to hear break in effects

 

[Danny Richie]

I count three relevant links posted above by Gene (plus one comical one),

I could post links to nay sayers from all over the Internet that think like you think too. That really doesn't mean anything. Factual data is not determined by getting a group of people together to vote their opinions on it and whatever the majority thinks is the way it is.

and anyone who thinks a piece of wire needs to break in does not, frankly, deserve the time of day.

Such statements like that certain speaks volumes about yourself. Anyone that doesn't believe what you believe can hit the road eh?

Here are my thoughts on the cable deal and then we can drop it. Debating it will go no where and is useless. The problem I see is more of attitude. That's the real problem, and you have demonstrated it very well.

I have put together plenty of speaker cables. There was a time that I have built an identical set. I used the same wire from the same spool and they got the same type of ends from the same bag.

I placed one set of cables in my system and played them for many weeks.

My initial thoughts were that they seamed a bit bright, edgy, sharp, and were hard to listen to. I didn't really care for the sound. Of coarse that character changed as more time was put on them. After many weeks of play they sounded pretty smooth.

So then one day after an hour or more of listening, I dropped the other set of cables into the system (the other identical pair). The sound was very different than the well burned in pair. It was harsh sounding, bright edged and fatiguing just like the other one was weeks before.

I'd also have to say that the differences were easy to discern.

Have I witnessed a difference in sound due to burn in on cables? Yes I have.

Now I don't tell this tale to prove anything. It doesn't mean that you or anyone else will notice the same things.

The point is this. Who are you to tell me that I can't hear? What makes you think that you or anyone else can tell someone that they don't deserve the time of day because they have experienced something that you have not.

The only thing that you can factually say is that you have not witnessed such.

You see, its the poor attitude that is the fuel for fire.

Now as to your questions:

If speakers break in, don't they also break-down?

There reaches a point in which they settle in and there is hardly any measurable differences due to extended play. You'll see 95% or more in the first 40 to 50 hours of play unless they are played very lightly and not worked hard.

Does the frequency response not continue to change over time?

Frequency response changes little over time and is hard to discern. Fractions of a db in amplitude are not really detectable. You really won't know whether you have even turned the volume control up to the exact same place twice.

How quickly? If not, why would it suddenly stop? Where are those measurements?

Again the burn in process has little to no effect on amplitude.

Look at it this way. I have two woofers that have different types of cone materials. They look the same through a given pass band where they are used. I mean that they measure the same. But they don't sound the same. The materials used are different and they have a slightly different sound. Most people will accept this.

Now I have two woofers that use the same cone material but the compliance is different. Funny thing is that they sound a little different too. It could also be that the compliance was the same before one was burned in a bunch.

Why aren't manufacturers selling extended warranties and opening up shops for replacing drivers after a period of time to keep the speakers within spec?

What makes you think that they are out of spec once they have burned in? This may be what is necessary to bring them into spec as fully burned in drivers were used in the design phases and voicing of the speakers.

Ok let's get back to the topic of speaker break in and put the cable snake oil debacle on hold for now.

Agreed. Let's have a look at what your buddy had to say.

It was pointed out that despite the mention that he "heated up the coil" he apparently didn't remeasure DCR while hot as he reports it as being the same in all measurements.

The voice coil is vented through the pole piece and through the frame. It also uses a Kapton former. It doesn't got hot like many voice coils would. But let's say it did get hot and it dropped the DCR from 5.6 to 5.5 ohms. This is practical.

DCR is of coarse a figure that one must input just like Sd.

Here are the figures from the test when measured hot with the DCR set at 5.6ohms.

Fs 48.2417
Fs Added Mass 23.8606
Added Mass 25.0000
Diameter 110.0000
Z F1F2 14.2580
Re 5.6000
Rms 1.2673
Qms 1.9365
Qes 0.3532
Qts 0.2987
Cms 1.3443
Mms 8.0965
BL 6.2377
VAS 16.9529
dBSPL 89.3374
L 1kHz 0.3228
L 10kHz 0.1809
SD 0.0095

Now here they are again with 5.5 ohms input.

Fs 48.2417
Fs Added Mass 23.8606
Added Mass 25.0000
Diameter 110.0000
Z F1F2 14.1302
Re 5.5000
Rms 1.2646
Qms 1.9407
Qes 0.3465
Qts 0.2940
Cms 1.3443
Mms 8.0965
BL 6.2411
VAS 16.9529
dBSPL 89.4204
L 1kHz 0.3228
L 10kHz 0.1809
SD 0.0095

Looks like very little change to me. This is nothing at all compared to the change from running the woofer for 20 hours.

Vas and Qts are synthetic quantities so we tend look at Mass and BL which should not change. Clearly his data are noisy as mass and BL did change.

My data are noisy?

BL is a force factor derived from motor strength and mechanical compliance. Change the mechanical compliance and you change BL. Therefore, burn in time effects BL as is well known.

Mass is not measured on a gravity scale. It is derived from a resistance differential. Change the resistance and you change the Mass. Resistance is changed by compliance changes. Compliances change with burn in. So Mass figures can change as well.

The change in FS he reports and some level of recovery is real. We often see FS moving around a bit depending on temperature and break in. Surround material and design makes a huge difference. Some materials and designs are very stable.

I agree. I wonder if the break in period he refers to is many hours (as do I) or if it is within the first ten seconds as this site supports?

Some materials are more stable from the get go and some go through a period of change in the early hours of burn in and then become very stable.

Hot voice coils heat the air in the enclosure, thus heating the cone and surround and changing their mechanical properties

This is true as well, but I did not burn my woofer in by playing it in an enclosure.

temporarily for the most part, but with the witches brew of materials used in paper cones, it is conceivable that there are instances where some of it could be permanent. For other cone materials, the effects are temporary (existing only while the material is hot), if they exist at all; which is why we look for cone materials that maintain similar mechanical properties over a wide temperature range.

A witches brew of materials. That was funny. I don't see cone material getting hot from a voice coil especially a paper cone. Paper is an isolator. Now a metal cone is a different story. Metals are of coarse a conductor of heat. Plus, changes seen in compliance are not from effects on the cone.

Measured changes in LF output as a result of all of this tends to be of the order of 0.5 dB around 50Hz. As I said, in a room this has to be close to or below the threshold of audibility, but since competent designs account for it, it is not an issue.

It can actually be several db of change, but I also agree that this is not the source of the changes in audibility.

So it appears to me that if you have a poorly designed paper cone then the extent of break in will be more pronounced.

Now my design skills are poor? This again shows ignorance, and is insulting. The woofer tested is a well known favorite in the audio community. Its performance is well in excess of its cost and it is highly regarded. It is also used by several other loudspeaker companies and was selected for its performance.

For what it is worth I have worked with drivers from nearly every major driver manufacturer in the business. Rarely do I see a higher level of QC than that of the driver that I tested. Other standouts would include the several hundred drivers that were built for me by Eton a few years ago.

 

[Tomorrow]

Now my design skills are poor? This again shows ignorance, and is insulting.

(Knock Knock).....Oh, 'scuse me...I was looking for the Steam Vent...got lost...

 

[j_garcia]

Red chicklet for you then...

 

[Dan Banquer]

Speaker Burn In

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.

Please note that Steve Lampton is a rep for Belden who is a rather large manufacturer of wire. He doesn't believe in wire burn in either.

There reaches a point in which they settle in and there is hardly any measurable differences due to extended play. You'll see 95% or more in the first 40 to 50 hours of play unless they are played very lightly and not worked hard.

To date I have never heard this effect. Please note that I have rebuilt speakers with new drivers and crossovers. I also have never heard capacitor break in for speakers either. If capacitors are really breaking down that fast, and I doubt they are, then you should investigate a different vendor. I also have never heard wire break in either, and I have been listening to the same stuff for years. I even cleaned all my connectors this past winter and I somehow managed not to hear a difference in that either.

One last note: I am industry professional and I also contibute to this web site with an occasional technical article. Seeing posts from you on this site really makes wish that John Dunlavy and Bud Fried were still alive and monitoring your posts on the web.
Now that would be refreshing!
d.b.

 

[Danny Richie]

Somehow Dan, I knew I'd see you here soon.

To date I have never heard this effect.

What you quoted was referring to a measured effect not an audible one.

I also have never heard capacitor break in for speakers either.

And Dan, I completely believe you.

If capacitors are really breaking down that fast, and I doubt they are, then you should investigate a different vendor.

No, its break in Dan, not break down.

I also have never heard wire break in either, and I have been listening to the same stuff for years. I even cleaned all my connectors this past winter and I somehow managed not to hear a difference in that either.

I believe you again.

Seeing posts from you on this site really makes wish that John Dunlavy and Bud Fried were still alive and monitoring your posts on the web. Now that would be refreshing!

It's funny that you mention John Dunlavy. I spent a great deal of time with him one day at his facility. He was one of the nicest guy I have ever met in this industry. He also showed me some rather interesting right angled flat wire that he was working on.

Funny thing now is that I have upgraded several of his speakers.

Simply replacing those cheap Solen poly caps and sand caste resistors with Sonicaps and Mills resistors really turns those speakers around. A lot of the smearing goes away. Resolution and detail level come right on up too. I have had some very happy SV4 customers. One was ready to get rid of the speakers but loves them so much now that he may keep them forever.

 

[WmAx]

Simply replacing those cheap Solen poly caps and sand caste resistors with Sonicaps and Mills resistors really turns those speakers around. A lot of the smearing goes away. Resolution and detail level come right on up too. I have had some very happy SV4 customers. One was ready to get rid of the speakers but loves them so much now that he may keep them forever.

Please refer me to the perceptual research demonstrating audibility of 'high-end' resistors, capacitors, and the wire break-in that otherwise have the same basic parameters as their 'low-end' counter-parts.

You have so far made several claims of audibility, but you seem to imply that they are fact, but you have not provided scientifically valid evidence to support these claims.

RE: Wondering why some people automatically dismiss what you say: When one makes speculative claims, implied as fact, one perhaps should not wonder why people in the actual scientific realm of the industry may automatically find one non-credible, since one is not evidenced as being critical in an objective manner.

-Chris

 

[mulester7]

.....it's been my experience for a new woofer to be as tight as it will ever be when you get it....then it's a matter of wearing out the excursion over a few years if you go reference levels fairly regular....there may BE a change at one month, or one year or three years, but it's not getting better, only looser.....

 

[Danny Richie]

Please refer me to the perceptual research demonstrating audibility of 'high-end' resistors, capacitors, and the wire break-in that otherwise have the same basic parameters as their 'low-end' counter-parts.

Show you objective data recorded on subjective analysis. If you can't hear a difference or have never heard a difference then there is nothing that I can tell you that will change your mind can I? Subjective reviews of components can be found all over the Internet. What difference does it make if a ton of people all say that they can hear a difference if you won't believe it.

Is it all about LCR? A 6.8uF capacitor sounds the same as every other 6.8uF capacitor right? It is funny how people will dismiss all the other aspects of a component.

You'd be surprised at what can make a difference. Capacitors are a good example. Variances can include differences in dielectric constant, dielectric absorption, dissipation factor, dielectric thickness, film thickness, film material, types of termination, type of solder, connecting wire leads, charge and discharge rate, conductivity of the film, contact material, type of covering, etc.

I have done a lot of capacitor comparisons and have been sent plenty of caps just to be a beta tester for those caps.

I have heard differences in things that would sound ridiculous to you.

I once had a cap manufacturer send me three different versions of the same exact cap. The difference was only in the other covering. One was wrapped in what looked like tissue paper. One was wrapped in a poly cover but the ends were exposed, and one was completed sealed in polypropylene. Clearly the better sounding cap was the one wrapped in tissue paper. The one completely sealed sounded the worse. Of coarse the manufacturer already knew this.

I even had a cap manufacturer hand deliver me two caps. Each was a 6.8uF cap. Each was about the size of a soup can. Both were some type of a Teflon film and foil composite. One was slightly larger than the other but lighter weight. Both were very heavy. It was stressed that I do not drop them as each one cost $500. in materials cost to make them. They sounded unbelievably clean to say the least.

Now I am even crazier than you thought huh? All of that is really crazy. But what is really crazy is that people will except that two different speakers can sound different (they look different after all right) even though they may measure very similar. But two different types of capacitors made from completely different types of materials can't sound any different. Now that is crazy.

You have so far made several claims of audibility, but you seem to imply that they are fact, but you have not provided scientifically valid evidence to support these claims.

Oh no, my claims of audibility are nothing more than my opinion. The data that I posted shows fact. It shows the measured effect of burn in time on a driver. And I don't care if you can hear the difference in speaker burn in time or not. And I really don't care if you believe that I hear a difference or not, but I take issue with anyone telling me what I do or don't hear.

Wondering why some people automatically dismiss what you say: When one makes speculative claims...

Posting measured data is NOT a speculative claim.

 

[WmAx]

Show you objective data recorded on subjective analysis. If you can't hear a difference or have never heard a difference then there is nothing that I can tell you that will change your mind can I? Subjective reviews of components can be found all over the Internet. What difference does it make if a ton of people all say that they can hear a difference if you won't believe it.

I can point you to countless references of UFO abductees and psychic testomonies. What worth is testimony? Not much in the scientific field.

You'd be surprised at what can make a difference. Capacitors are a good example. Variances can include differences in dielectric constant, dielectric absorption, dissipation factor, dielectric thickness, film thickness, film material, types of termination, type of solder, connecting wire leads, charge and discharge rate, conductivity of the film, contact material, type of covering, etc.

And the audible relevance of DA, between a common Mylar/Polyester capacitor vs. a SoniCap, for example? Do you have any credible perceptual research to refer to?

Now I am even crazier than you thought huh? All of that is really crazy. But what is really crazy is that people will except that two different speakers can sound different (they look different after all right) even though they may measure very similar. But two different types of capacitors made from completely different types of materials can't sound any different. Now that is crazy.

There is no mysterious X factor that is non-measurable. No one has demonstrated such an X factor. But two different speakers should sound the same, if they are used within identical SPL levels, not driven to a point where non-linear distortion(s) would differentiate the two, used in the same position so that they interact with the acoustics of the environment identically, and have identical impulse responses, considering not just on-axis response, but also polar response. Also, most published measurements[such as those by DIYers and most magazines] do not have sufficient resolution due to the various conditions under which they are made in order to make visible critical resonances[ and the actual Q and relative amplitude so that it can be correlated with perceptual research to determine expected audibility weighting ] in the <1000 Hz range[peak resonance detection actually is in the 300Hz-500Hz range] of the entire speaker system[not just a nearfield spliced response of lower frequencies] that may otherwise not show up, due to the need to measure from a free field position on a pole away from surfaces, or be measured in an anechoic chamber, to avoid reflections before a sufficient gate time is achieved. Because of the variables involved, especially in respect to polar response, it is unlikely that one will match all of these parameters sufficiently to all be below human auditory thresholds between two different speakers. However, in the extraordinary rare circumstance, they may be very similar, and sound very similar[almost identical], but due to the inherent variables, I doubt they would sound exactly the same--just very similar--but within human auditory thresholds.

Oh no, my claims of audibility are nothing more than my opinion.

Then perhaps you should make this clear when ever you make a statement pertaining to such questionable audiblity claims. You would [my perspective, anyways] probably gain a lot more credibility if you were careful to make these qualification(s).

The data that I posted shows fact. It shows the measured effect of burn in time on a driver. And I don't care if you can hear the difference in speaker burn in time or not. And I really don't care if you believe that I hear a difference or not, but I take issue with anyone telling me what I do or don't hear.

I did not reply to anything that you said about driver break-in, one way or the other, therefor I do not know why you make this statement.

Posting measured data is NOT a speculative claim.

The speculative claims, I specified. I did not mention your speaker break-in.

-Chris

 

[Danny Richie]

And the audible relevance of DA, between a common Mylar/Polyester capacitor vs. a SoniCap, for example? Do you have any credible perceptual research to refer to?

Hey Minwax, I have done a ton of capacitor comparisons and research using groups of people, etc.

But two different speakers should sound the same, if ...

You barely even scratched the surface regarding what it takes to make them sound the same (from a measurements standpoint). Still, differences in material used will have a different sound to it. For instance, I have had identical drivers made with different cone materials. Then built identical speakers using each of them. Measurably they look the same, but the sound is very different.

I did not reply to anything that you said about driver break-in, one way or the other, therefor I do not know why you make this statement.

This is the actually topic that we got off of.

Hey guys, a known driver designer and manufacturer responded to my data. I added his response to the bottom of the page.

http://www.gr-research.com/burnin.htm

Hey Gene, Clint, and Mark. I have an idea. Since you guys have 100k worth of test equipment, why don't you measure the T/S parameters on a bunch of fresh out of the box woofers. Then measure them after 10's of seconds worth of burn in time (allowing for cool down). Then measure them after about 40 hours of hard play (allowing for cool down), and see if your numbers then match that of every other driver manufacturer across the world, or it they really only need a few seconds of burn in to stabilize.

 

[Audioholics]

Hey Minwax

Consider this a public warning to not toss insults. Next time you get a week off. Argue your case, not the person.

Posting your many hours of research results using the groups of people you claim to have tested would be more productive - assuming that was actually documented by you.

We've already posted our research and findings.

 

[Danny Richie]

What? I mess up on a guys name and I get a warning for insults? That was nothing. The real insults came when you guys insulted me by belittling my credibility as a known loudspeaker designer.

We've already posted our research and findings.

What research? You have nothing there. There is NO test data to be found. There are some figures there from some unknown drivers that might have come from published data somewhere.

Then as stated the "break in specs are derived from a 5% increase in suspension mechanical compliance. "

The data to support the change in compliance was "derived" from a 5% increase?

You took a VAS figure from a 4.5" midrange driver of 1.5627 liters and multiplied it times 1.05 to get 1.6408 liters.

That is your research findings?

Where is the measured data? How do they measure to begin with? How do they measure after X number of seconds, hours, etc.?

Then you take the derived data and run it through a LEAP software simulation.

You call that research? Come on man!

 

[j_garcia]

Using pseudo science to try disprove what you guys are calling pseudo science. I like that one. This is one of those debates that always ends up going nowhere. Regardless of data to support a position (or not), neither side will ever convince the other that one or the other is the definitive answer.

If you want to talk caps, I upgraded my speakers from Danny's company from the standard caps to the Sonicaps and there is a definite difference, subtle but audible. I have another pair that do not have the upgrade and basically everyone can hear the difference when played back to back - without telling them that there is a difference. Is that psychoacoustics? I think not.

I caught Sleestack's post before it was deleted, so I know what he is talking about too.

 

[Tomorrow]

Using pseudo science to try disprove what you guys are calling pseudo science. I like that one. This is one of those debates that always ends up going nowhere. Regardless of data to support a position (or not), neither side will ever convince the other that one or the other is the definitive answer.

If you want to talk caps, I upgraded my speakers from Danny's company from the standard caps to the Sonicaps and there is a definite difference, subtle but audible. I have another pair that do not have the upgrade and basically everyone can hear the difference when played back to back - without telling them that there is a difference. Is that psychoacoustics? I think not.

I caught Sleestack's post before it was deleted, so I know what he is talking about too.

John, is the difference in sound, in your (and the others that heard them) opinion, an improvement, a degradation, or so miniscule that it was not worth the change? Also, when you played the speakers for comparison purposes, how did you set them up for testing?