Do Audio Speakers Break-in?

[jeffhenning]

There is only one piece of audio equipment that requires break-in: woofers.

Everything else? No.

Woofers’ suspensions have a lot of excursion (unlike mids and tweeters). To get guy the suspensions to nominal compliance, you have to hit them with a strong signal that will stretch the suspension. A short burst around 80Hz from a tone generator or playback of one loud song will do it.

Done. The woofer is broken in.

Don’t believe me. Believe Andrew Jones (Chief Technology Officer for KEF, TAD/Pioneer, ELAC, MoFi). He explained this to that goof ball, Steve Guttenberg. Guttenberg was astonished and confused more than normal.

It doesn’t take weeks? No, it doesn’t.

The reason people think this is the case is because they feel the sound of the speaker is changing. It’s not. It’s actually their brain getting acclimated to the new sound. That’s it. The speaker remains the same.

Everything else people profess to need or improve due to “break-in” doesn’t. Again, rampant stupidity and ignorance being accepted as fact.

John Siau of Benchmark Media wrote me that people thinking his equipment was burning in were just getting used to equipment with much less distortion. Once you accept the new, better paradigm in sound, there is no going back.

Again, to the point of my previous post, your hearing just isn’t that good. It really isn’t.

My final thought is this: if all of your equipment needed to get broken in for weeks until it was at what would be considered it’s performance ideal, wouldn’t the manufacturer have to do all that break-in? If they didn’t, how would they know the equipment is even performing properly?

The whole notion of quality control would fly right out the window.

 

[kemmler3D]

There is only one piece of audio equipment that requires break-in: woofers.

Everything else? No.

Woofers’ suspensions have a lot of excursion (unlike mids and tweeters). To get guy the suspensions to nominal compliance, you have to hit them with a strong signal that will stretch the suspension. A short burst around 80Hz from a tone generator or playback of one loud song will do it.

Done. The woofer is broken in.

Don’t believe me. Believe Andrew Jones (Chief Technology Officer for KEF, TAD/Pioneer, ELAC, MoFi). He explained this to that goof ball, Steve Guttenberg. Guttenberg was astonished and confused more than normal.

It doesn’t take weeks? No, it doesn’t.

The reason people think this is the case is because they feel the sound of the speaker is changing. It’s not. It’s actually their brain getting acclimated to the new sound. That’s it. The speaker remains the same.

Everything else people profess to need or improve due to “break-in” doesn’t. Again, rampant stupidity and ignorance being accepted as fact.

John Siau of Benchmark Media wrote me that people thinking his equipment was burning in were just getting used to equipment with much less distortion. Once you accept the new, better paradigm in sound, there is no going back.

Again, to the point of my previous post, your hearing just isn’t that good. It really isn’t.

My final thought is this: if all of your equipment needed to get broken in for weeks until it was at what would be considered it’s performance ideal, wouldn’t the manufacturer have to do all that break-in? If they didn’t, how would they know the equipment is even performing properly?

The whole notion of quality control would fly right out the window.

Totally true. I did once try to measure burn-in on some headphones, back when I was in the biz. I had a factory-fresh sample that I burned in overnight at high SPL. Then I measured it against a set that was fresh-fresh. While the measurements were different, I was placing the headphones on a MiniDSP EARS jig by hand, and the delta was on the order of 1dB. I do not offer this anecdote as evidence of anything.

That said, our customers were convinced they needed many hours to burn-in. I did that test mainly to humor them. Undoubtedly it was just their ears / minds adjusting. Even if the measurement I got was real (it was a paper cone with flexible surround - not sheerly inconceivable) it would have been really hard to hear in a non-fast-switching A/B test, let alone day-to-day on the same set.

There is a really good reason to promote the idea of burn-in, though.

As you say, it's our brains adjusting to the sound of the new gear.

If people get something out of the box and don't like the sound, they might return it. If you convince them it needs "burn-in" instead, they'll spend many hours playing sound through it.

This will result in a dramatically lower return rate. One, because people adjust to the new sound and decide they like it after all. Two, because the longer people keep something in their house, the less likely they are to package it up and send it back. That's just a universal trait of shipped goods.

Convince them it needs >150h of burn-in to sound right, and among the people that do it, you should expect a tenth of a percent returns, if that.

 

[jeffhenning]

You know, that never occurred to me. Now that you mention it, though, it makes perfect sense.

In fact, that may be the genesis of the entire burn-in myth. Whether it’s brick and mortar or e-commerce, no retailer wants to get returns. They want the stuff they’ve sold to stay sold.

 

[MAB]

Agree.
Break-in effect is exaggerated in speakers.
For instance, Floyd E. Toole, Sound Reproduction - Loudspeakers and Rooms, Chapter 17

 

[Chrispy]

You know, that never occurred to me. Now that you mention it, though, it makes perfect sense.

In fact, that may be the genesis of the entire burn-in myth. Whether it’s brick and mortar or e-commerce, no retailer wants to get returns. They want the stuff they’ve sold to stay sold.

Or just push it beyond the return period

Even with woofer compliance changing a bit, measure a few days later and its probably back at the starting point again

 

[kemmler3D]

Or just push it beyond the return period

Even with woofer compliance changing a bit, measure a few days later and its probably back at the starting point again

This will depending on the product, but the return rate drops quickly day-by-day regardless of the return window.

I always tell entrepreneurs in consumer goods to offer the longest return window they can wrap their heads around. When I've tested this, extending the window doesn't increase the return rate. In fact, extending it can sometimes LOWER the return rate, since people don't feel pressure to return something if they have a "cushy" window, and then they gradually lose motivation to return it.

So burn-in is actually (depending on your point of view) very clever product marketing, or an evil scheme to trick people into keeping equipment they should have returned.

 

[YSC]

This will depending on the product, but the return rate drops quickly day-by-day regardless of the return window.

I always tell entrepreneurs in consumer goods to offer the longest return window they can wrap their heads around. When I've tested this, extending the window doesn't increase the return rate. In fact, extending it can sometimes LOWER the return rate, since people don't feel pressure to return something if they have a "cushy" window, and then they gradually lose motivation to return it.

So burn-in is actually (depending on your point of view) very clever product marketing, or an evil scheme to trick people into keeping equipment they should have returned.

The best part of the strategy is that the inventor lets you adapt to the product, especially when it cost an arm and a leg, so they must be good! Seriously, for those abusing the return window policy I could only think of expensive clothings where abusers just buy it, dress it to ball for a night and return the nextday, or things like cameras lens, maybe one event need a specific lens which they will not use afterwards, so buy it, shoot for the event and return. other wise once you get and adapt to the product for a few days, it will likely never be returned

 

[jeffhenning]

My post was about the myth of break-in, not loudspeakers.

You totally missed the point of it and apparently did not actually read it.

 

[MAB]

My post was about the myth of break-in, not loudspeakers.

You totally missed the point of it and apparently did not actually read it.

I was posting a general observation from Toole, since my ears were still ringing from the OldHvyMech bellowing obscenities and nonsense.

I think Chrispy acknowledged that the myth is used to push customer's outside of the return period, which is exactly what you said too. So, perhaps there is this internet misunderstanding factor.

Also,

There is only one piece of audio equipment that requires break-in: woofers.

Everything else? No.

Well I tested a bunch of drivers and actually published the data in this thread. Large woofers, midbass, small micro speakers. And tweeters.

In fact, midranges and tiny speakers like the HiVi B3N actually have much larger break-in effects than a traditional woofer. The reason has to do with the relatively low compliance relative to the cone mass. The tiny cones and low mass means a small change in spider stiffness has a larger effect on the overall parameters.
Woofers as a class of speakers actually barely break in, for a woofer to show significant break-in it has to be a bit of an oddball like those micro-HiVi, and have unusually stiff suspensions (I have used many HiVi in the past, the B3N that I have are incredibly stiff and make lots of mechanical noise when playing, so not exactly a stellar example and not a driver I would purchase again - like I said more of a corner-case). So, I would say all speakers break in, just not very much.

Agreed with everything else, these small changes to the suspension happen in the first few moments of operation, just as Andrew Jones and others have observed. And environmental effects like room temperature have a larger effect.

 

[cavedriver]

Recent example of measured, documented woofer break-in that reminds me of my experience with an old Infinity Kappa car woofer. Again, here the idea is that you have a woofer that has been sitting on the shelf, possibly for years, giving the spider and surround time to sit and possibly harden up. The effect probably varies widely by construction method, whether the factory did any breaking in, and the storage conditions, but the theme is consistent with may others' comments in this thread- yes it is real for some drivers, but the effect generally wears off in hours or less, not days.

Evidence of Driver Break-In Captured

I was starting on a new speaker design using a Fostex woofer from their NX6A powered monitor. This 6.5in driver has a unique pinched cone and wrinkled surround, similar to the Purifi woofers. I got the bare drivers about 3 years ago for a blowout sale ($15 IIRC). Since these are not currently...

www.diyaudio.com

 

[YSC]

Recent example of measured, documented woofer break-in that reminds me of my experience with an old Infinity Kappa car woofer. Again, here the idea is that you have a woofer that has been sitting on the shelf, possibly for years, giving the spider and surround time to sit and possibly harden up. The effect probably varies widely by construction method, whether the factory did any breaking in, and the storage conditions, but the theme is consistent with may others' comments in this thread- yes it is real for some drivers, but the effect generally wears off in hours or less, not days.

Evidence of Driver Break-In Captured

I was starting on a new speaker design using a Fostex woofer from their NX6A powered monitor. This 6.5in driver has a unique pinched cone and wrinkled surround, similar to the Purifi woofers. I got the bare drivers about 3 years ago for a blowout sale ($15 IIRC). Since these are not currently...

www.diyaudio.com

For this case I can see the only meaningful break in was at like 1min mark, but you won't know if that's something in the voice coil getting rust or other stuffs breaking away or the surround loosening, for drivers sitting on shelf for extended period of time, I would personally be more skeptical on the degradation of soft suspensions, rubber from extended non-stressed environment can crack and irreversably damage, metal parts if exposed to moisture or even salt will oxidize.

 

[MAB]

Recent example of measured, documented woofer break-in that reminds me of my experience with an old Infinity Kappa car woofer. Again, here the idea is that you have a woofer that has been sitting on the shelf, possibly for years, giving the spider and surround time to sit and possibly harden up. The effect probably varies widely by construction method, whether the factory did any breaking in, and the storage conditions, but the theme is consistent with may others' comments in this thread- yes it is real for some drivers, but the effect generally wears off in hours or less, not days.

Evidence of Driver Break-In Captured

I was starting on a new speaker design using a Fostex woofer from their NX6A powered monitor. This 6.5in driver has a unique pinched cone and wrinkled surround, similar to the Purifi woofers. I got the bare drivers about 3 years ago for a blowout sale ($15 IIRC). Since these are not currently...

www.diyaudio.com

Putting aside the measurements which I looked at.
Can you hear a reduction in distortion on this order?
And did it actually go down?

It went up on the no-vent experiment. I would suggest that they actually did a vent/no-vent experiment and saw distortion go down due to the addition of a port. Along the way, they likely suffered from experimental setup (distortion measurements are highly sensitive to mic position, see below). Certainly run1-run4 look like common setup (FR is matched). Run5 and run6 look like the setup changed since FR and distortion now have changed. Or is it because the driver got hot, this is where it gets fuzzy, reading the post I see warning signs:

Seeing the THD go down a bit, I tried running 45Hz at about 2.8vrms for 1 min to see if this loosened up the suspension: And it sure did!
So I tried leaving the 45Hz on for 60 minutes - distortion at 300Hz went down to about 34dB an apprximate 30 dB improvement!

If the DIYAudio measurements are right after these stresses, the driver is hot and we are now measuring temperature effects, not material changes due to use! And to be clear, it takes several hours for a driver to re-equilibrate to ambient after just a few minutes of applied power (I show this over and over earlier in this thread!) I can't tell if the mic position changed or the driver is hot, the evidence I see suggests both changed, but I don't want to guess. Distortion measurements are really sensitive to mic position to within mm. Hard to keep constant setup, especially when you are simultaneously mucking with ports.

I guess you could say the reduction in 5th HD from Run1 to Run2 might be the spider relaxing and actual evidence of break-in. But it's hard to jump to that conclusion since I also can't explain Run5 5th HD which went way down! In reality, this is liklely run to run noise. I do expect spider to relax in the first few moments. But the effect is darn hard to measure, and I do wonder if that non-linearity would show up in distortion measurement as claimed in run1-run2.

Lots of things changing in this experiment, distortion is the last thing I would use in this case unless ultra-careful about setup. Using distortion to measure mechanical changes in a driver is fraught. First order would be to measure the TS parameters since they are going to be most fundamental. Then see how it changes FR. And along the way measure distortion to see if it can help explain. And for sure, these distortion measurements look like rather run to run setup changes, not break-in induced distortion reduction.

To show why I am skeptical of distortion measurements, here are some I just made on a woofer that is well broken in. The mic is nearfield (5cm). I changed the mic position by moving it ~5mm off-axis from the woofer's centerline, making sure to keep the distance the same. I also changed the angle a bit in the process, not intentionally but I noticed it slightly angled after my fussing. I get matched FR as I would expect for such a small change.

I get different distortion:

5mm change in mic centering on driver.

I got almost the same effect as the DIYAudio post just by bumping the mic! I did have mismatched noise, I think a car drove by down the hill from me... But I would never hang my hat on a distortion measurement as a metric of a driver's break-in performance. I won't speculate on what is happening that changed the distortion in my measurements, but it sure isn't break-in.

I can't come to the same conclusion as DIYAudio, in fact distortion actually steadily increases with time in the no-vent experiment! And goes down with a vent (yes, we all expect a vent should slightly lower distortion!) But no trend I can see. It they had measured driver impedance traces and TS parameters, it is likely they would have seen the spider relax in the first few moments of operation, saved a ton of time, and not led themselves into he weeds with this distortion.

 

[cavedriver]

Putting aside the measurements which I looked at.
Can you hear a reduction in distortion on this order?
And did it actually go down?

One thing I'm not clear on is whether the numerical values at the bottoms of the graphs are for the full frequency sweep or just the 150 to 4k Hz range where the most visually striking changes are occurring. Had the data been filtered for that range a different set of values might be recorded.

 

[moonthink]

I don't mean to argue for or against mechanical burn-in of speakers or other components, but I did want to share my own recent experience with burn-in that definitely opened my eyes (or rather, ears)...

I had (and still have) a pair of Wharfedale Denton 80th Anniversary speakers that I loved. I'm still not entirely sure what I found so special about them, but when I found a deal on a second set -- I grabbed them, then reached out to Amir to see about getting one of them tested. The results were not so good, and I was more than a bit surprised, and that made me really wonder what it was about these speakers that made them seem special to me. So I decided to get some speakers that measured better, both to compare with the Dentons, but also to see if I could identify what factor made them seem special.

First I got a pair of Diamond 12.1's and they were decent considering their price, and seemed mostly similar to the Dentons (other than the Dentons' boost around 4-6k, which I think I may have some reduced hearing in that range, which might explain why they stand out to me) but the 12.1's still seemed to be missing something (bass probably). Looking back, I don't think I gave them enough time for me to adjust to them.

Next I got a set of Revel M16's. Right out of the box, these sounded more "special" than the 12.1's, but I really had a hard time living with the bass bump around 100Hz. Occasionally, I'd go back to listening to the Dentons, which I had set up in another room. Still loved them.

Fast forward about 2-3 weeks... I had only listened to the M16's in that time. First, I had to cut the bass on my tone controls by -2. Then I tweaked placement and positioning. After about a week, the bass seemed lacking, so I dialed it up to -1. Most recently I can keep the bass at 0 for most recordings. It sounds really good, but to be honest, still slightly lacking a bit of that intangible specialness factor of which I have yet to identify.

So last night I realize I haven't listened to the Dentons in a while, so I spend the evening up there. Suddenly they seem to be overly bright (which they are, as measured) and slightly lacking in bass (the 100Hz bump that I am now used to). Other than a shimmery sounding wide stereo imaging, they sounded pretty awful. I couldn't believe it. I mean, well I could believe it, but I was shocked at how drastic the difference was based on only a couple of weeks in a different listening setup.

tl;dr
Burn-in is a very real experience, but it occurs in your ears/brain.