There are a lot of "everybody knows" type of rules in audio with one of them being that audio gear in general, and speakers in the specific, benefit from "break-in." That is, their performance improves after some time. This is mostly touted by audiophiles but manufacturers also fuel this notion. See this from Klipsch's website:Kind of strange that a company like Klipsch that knows how to measure speakers, doesn't provide a single bit of validation for this statement. You are just told to believe.Why shouldn't we believe? I remember just about every new car I purchased said in the manual there was a break-in period and I read in auto magazine that after their long term test, mileage improved and so did power. In the case of speakers, they are made out of material that like any leather glove, can surely benefit from use to soften and fit like well, a glove. Are we supposed to all of a sudden throw out all this common sense and listen to a bunch of "objectivsts" telling us otherwise on some Internet forum? Surely not.Heck, there are even measurements that show drivers like woofers change their characteristics after a few hours of "run in." Objective proof doesn't get better than this. Or does it?Well, it is true that drivers change behavior after a bit of use but once you put them in a compliant box of a speaker, those differences become minimal. And certainly don't rise to the level of improvement people talk about. We could and usually stop here as the end of our argument but let's add some data, shall we?A couple of days ago I reviewed the Revel M16 speaker . Anxious to get quick results, I ran the test with 500 measurement points. For a 2-way speaker with clean implementation, that should be enough. When I compared the results of my measurements to Harman's anechoic measurements, I noticed that the high frequencies were rolled off in my test versus theirs. This can happen with my measurement system is the "expansion order" is too low. To increase that, I needed to measure the speaker again with higher number of points. So I doubled the measurement points to 1000 and ran the test again without touching the speaker or any other parameter.The first 500 point measurement took about an hour and fifteen minutes. The second test took over 2 hours. If there is anything to break-in, then the second test should sow some improvement. Here is the comparison:The two measurements are essentially identical. This, despite the fact that the 1000 point measurement has much higher order expansion so brings with it more accuracy and some variations. Yet, the response is still the response. No way anything regarding tonality of the speaker changed. The same bass, mids and highs are there.While I did not listen to the speaker between runs, I did listen to it after the second test. At that point, there was 3 to 4 hours of run time on the speaker. I compared the M16 to my Revel Salon 2 which have played hundreds or thousands of hours of music. The M16 very closely resembled the sound of the Salon 2 sans out level capability and deep bass. So no way is anything broken about it right now to need to improve.Objective analysis shows that there is no change to the frequency response and hence tonality of the speaker after a few hours of intensive running (full sweeps from 20 to 20 kHz). This completely mirrors research performed at Harman where they tested a new woofer and a "broken-in" one in a real speaker. While physical changes are occurring in the driver, they are at such low level that there is no hope of attaching them to audibility.Of course our perception of audio is not just connected to sound our ears pick up. Many other factors come into play from our faulty long term memory to allergies and mood. These are responsible for variations we hear even when nothing of import has changed in the system.Manufacturers either genuinely believe in the speaker break-in myth, repeating what they have falsely concluded like audiophiles. Or are hoping that if you don't like the speaker at first, you hang on to it longer to lose the motivation or option to return them later. Either way, there is no reason to listen to them unless they provide objective proof that sound changes with break-in. After all, this is no small difference so surely they can measure and provide proof.------------As always, questions, comments, recommendations, etc. are welcome.Now that I have saved you a ton of money from myth of speaker burn-in, how aboutsome of that to me so I can run more of these tests using