All drivers need to be "Burned-In", really?

Has anyone ever heard of "burning in" new speakers? Many audiophiles said the new speakers should be "burned in" for about 200 hours before their sound is stable. This is widely accepted.

But for the old drivers that have been refurbished, are they required to be "Burned-In"? This question links to my previous post that my old woofer had a new alignment—disassembled the moving parts and reassembled them at their center. And its sound was changed after the alignment. So, I wonder if they need to be "Burned-In".
 
When new driver is assembled the spider and surround depending
on how it is treated will be a little stiff and take few hours of operation
to start loosening up.
Out of the box Fs can be little higher and mechanical properties
will vary.

Longer break in time is more towards according surround.
Rather treated paper or cloth is sealed with black goop.
So takes a little time for the surround to work in.

Far as foam or rubber surround. not really
more just the spider. not many hours

older driver with worked in spider and surround.
already burned in.
 
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It is a good idea to run them in for few hours near or at fs, often feeding anti-phase signals to a pair, in order to reduce the audible sound coming out of the setup. Some companies do something like this for you at the factory, but I'm not sure of which ones do so (or not).
 
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TNT

Member
Joined 2003
Paid Member
Burn in is not a option. As you play them for the first time, they will "burn-in" - there is no way out of it i.e. you can't avoid "burn-in" less you never use them. Good luck.

PS. All mechanical items will be effected by being used and while that happen, their mechanical properties change. Like a tire will be a poor one after when all tracks are worn down....

//
 
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You absolutely need to "exercise" a new driver for a while to get stable TSPs in order to get the enclosure alignment close to what it will be for the rest of its operational life. There's some give and take with this as Vas will usually go up while Fs goes down, and Qts has some variance as well. Typically you end up with higher box tuning until the parameters settle in. That can make a drastic difference in midrange and low end response.

I've seen people manually push cones in and out by hand to accelerate the break-in process, but this results in more uneven Kms which actually increases odd order HD. I did an experiment once with some Peerless TC9 drivers to try quantifying this and I was surprised how different they sounded between the driver that was exercised by hand rather than running a larger amplitude low frequency sine wave through the driver for several hours. I wish I could have documented this for others to see.

My preferred method for cone driver break-in is using a low frequency sine wave set at target Fs, incrementally ramping up the amplitude to 1/2 xmax for 2 hrs. Pushing the driver too hard too soon isn't good unless its a very beefy design with a double spider and large half roll surround. Accordian style surrounds need more time to settle in because they act more as part of the driver's emissive surface in the mids. These require more gradual break-in time with lower amplitude signals.
 
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It is certainly worth asking the question; there are audiophile myths about all sorts of things breaking in, though often with little evidence of them actually doing so beyond subjective perception (so simply their perception that is changing).

However, in this case it is very true; drivers really do change during initial use or 'burning in'. Different driver models and designs take different amounts of time to do so. IMO when their Thiele-Small parameters stop changing noticeably (e.g. over several days with normal use, probably much less with forced sine-wave methods) then they're sufficiently broken/burned in to measure and design for.
 
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If it weren't for experience more than once of driver break in, I wouldn't be so convinced. It hasn't happened with all drivers that I have purchased, but the most dramatic case was with an Audio Nirvana 12". Wow, it sounded really harsh, bad everything all at once. After maybe only 2 hours of plying it was a little better, but man, I wanted to send them back. Maybe after say 6 hours more of play, I could stand to be in the room with them and I wasn't gun shy. In the end they weren't my favorite drivers. I will say though that certainly had their merits in the mid range frequencies. A different cabinet would likely have helped with bass too.
On the other end of the spectrum, I am using a set of Scan Speak drivers in probably not the right cabinet (it was a no choice situation). They have way too much bass, and only recently, have they changed at all. Still too much bass, and so, I must make a better cabinet for them. Rear loaded horn is over the top. The drivers themselves do sound a little different in the mid bass now but that is about all to report. Not many hours on them yet, and in this case, the power amp driving them will make a difference.
 

GM

Member
Joined 2003
Yeah, the pioneer's drivers typically had a high Vas, minimal Xmax/Xmech, ergo box controlled, so basically a waste of time, but as amp power increased, drivers needed more powerful motors, stiffer suspensions, so smaller boxes ergo requiring ever more break in for wide BW use.
 
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When I first heard my AN15 Alincos I was listening to a female vocalist. It was the closest I had ever been to a you are there experience, but the rest was not so great. I don't recall how long it took to burn them in, but the difference was stunning.
 
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This totally depends per brands unfortunately. There are brands that make sure that drivers meet a certain spec and criteria.
Which often includes in house "burn in".
But most of the time it's rather minor and only will loosen up the Cms, and therefor to low end a bit.

It's rather difficult to really check, since so many manufacturers make their own little mess about how to determine T/S parameters.

The vast majority of "opinions" of people are just parroting stories with some weak theoretical idea behind. Very little real hands-on experience with significant amount.

In the end it even really depends what you want to define as "burn-in".
Certain materials act very different under certain mechanical loads and types of load. Therefore their (long term) dynamic performance can be very different.

I think Novak has some very interesting papers on this?

So the short answer is: it depends, but certainly not for all loudspeakers.
 
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Who has ever heard this opinion voiced: "My speakers sounded pretty good when I bought them, but now they are burnt in they sound awful and I'm looking at replacing them"?

Yes, speakers' measured parameters do change measurably as mainly the surround and spider(s') characteristics change. Strange then in the world of hifi that speakers never seem to become worse as they 'burn in', and only improve over time like a fine wine...
I remain completely unconvinced that this much-parroted procedure (with little - usually zero - applied rational thinking/data collection/science) is essential for best performance, and suspect that any 'improvements' in sound quality with use are almost entirely subjective on the part of the listener, being considerably more likely to be psychoacoustic acclimatisation with their new, often expensive purchase (with the attached expectation bias) than any sound quality enhancing mechanical changes.
 
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Yes, speakers' measured parameters do change measurably as mainly the surround and spider(s') characteristics change. Strange then in the world of hifi that speakers never seem to become worse as they 'burn in', and only improve over time like a fine wine...
Within reason (note caveat ;) ) not so surprising since the enclosure alignment should have been done based on the EM behaviour of drivers when the suspensions have reached their intended operating window, in which they should remain relatively stable over an extended period before the inevitable long-term wear & tear kicks in. For a reasonably heavy-duty unit, that should be a few minutes if you're able to run them at full-chat. For a low-mass unit with a relatively fragile cone, which also has relatively extended travel suspension, then it can take longer, since they're not meant to be continually flogged to high levels & you'll risk damage if you do so. Ye olde mechanical engineering, no more. Unfortunately, like a lot of things, there's a tendency for it to be overstated.
 
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This totally depends per brands unfortunately. There are brands that make sure that drivers meet a certain spec and criteria.
Which often includes in house "burn in".

It's rather difficult to really check, since so many manufacturers make their own little mess about how to determine T/S parameters.
Well, some manufacturers exactly state the mess in which the parameters are measured, for example, the following is from JBL (pro):

1689176743812.png
 
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^ A conjecture that might be statistically true, but if probability is involved than that also would seem to imply its probably not acclimatisation in 100% of cases.
Agreed, which I why I never speak or write in absolutes. I suspect it is folklore that has been repeated and re-repeated so often that it has become cold hard fact, 'proven' by countless of pairs of imperfect ear/brain combinations hearing what they wish to hear! This happens in every field in which I have become involved at more than a cursory level - I wonder if there is a proper name for it...
 
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