Break-in period for new speakers - sealed boxes

I am an engineer, and familiar with the breakin characteristics of elastomers used for shock mounts and for speaker surrounds. I think that speaker breakin changes are related to changes of the properties of the surrounds, principally softening. This will usually result in better LF response, both frequency extension, and sonic quality.

The "conditioning" process (a better word than "breakin") depends on how much the elastomer is flexed as well as how long you do it. If you set your speakers going with a reasonably loud LF warble test signal in the morning when you go to work there should be a noticable improvement when you come home. If you just play music it could take many hours as you suggest.

Disclamer!! (These seem to be popular lately). I don't believe in breakin...except for speakers and phono pickups.

The suspension on all of the drivers will loosen up with use, but the drivers that will change the most in terms of electro-mechanical measurements and acoustic output will be those that make the longest excursions i.e. the woofers.

My basic suggestion is to play track #7 on the Ayre Acoustics disc entitled "Irrational But Efficacious" on repeat for as long and often as you can. If you aren't home, leave it on repeat and turn the volume up. If you're sleeping, let it play but at low volume. Some signal passing through the speakers or component being broken in is better than none.

Before doing this and leaving the house, i would HIGHLY suggest watching the woofer before picking some arbitrary volume setting. With sealed speakers, this is not as big of a deal as when using vented speakers. Due to the fact that this disc starts out with a tone at 5 Hz and climbs up from there, vented designs risk the potential for over-excursion of the woofer. This is because the woofers are "unloaded" i.e. there is no "air-spring" in the cabinet. Sealed designs have have a natural "high pass filter" built in and are far more secure in such a situation. As such, pick a volume that gets the woofers moving quite noticeably, but don't go gonzo right off the bat. After a day or so of this, you can increase the gain and really watch the woofers dance.

After rebuilding my Fathers' speakers a short while ago, we ran this track for 3 days straight at good volume ( he wasn't home ). By the end of the third day, the sound coming out of the speakers was nothing like what we heard the first day. After hearing the difference in sound, my Brother insisted that i had made other changes i.e. he had thought for sure that i had changed cabling, etc... We continued playing this track for several more days, mixing in various music discs for a total of two weeks of "burn in". When all was said and done, you would have thought that we had replaced the entire system with components that were 50% - 100% more expensive. Bare in mind that all of these components are several years old with the speakers having appr 15 - 17 years worth of time on them. Sean
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Sean I own this disc and respect your knowlege. At low volumes playing this disc on repeat, are you absolutely certain this will not put un do stress on all of your electronics, cables, amps etc ? Have you ever spoken to Cardas / Ayre about this ? Thanks !

We've had this disc playing up into the 90+ dB range for multiple days non-stop. So long as you have well built gear with adequate ventilation, this shouldn't pose a problem at all. It would be no different than playing very wide bandwidth music on your system. The difference here is that the system is only being fed a sweeping signal of limited bandwidth rather than a dynamic signal that is broadband in nature. While this does concentrate the energy applied to a very specific part of the spectrum at any given time, compare that to having hundreds / thousands of notes spread out all over the place in the same amount of time when playing music.

As mentioned, those with vented systems will have to pay attention to the woofer. If it looks like the woofer is going to pop out of the basket, it probably is. Back the gain down to achieve "good" throw out of the woofer, but don't drive it into "redline" right away. Bare in mind that the first five seconds of this track are silent and then it starts sweeping at 5 Hz and works its' way up.

Talking to Ayre may get you a different point of view than what i've mentioned here. I've used this on several systems and the results have always been VERY positive. Even systems that had high mileage on them. Then again, i try not to work with under-designed gear that is installed poorly. This is not to say that Ayre gear is "junk" ( NOT at all ), but that they may not want to assume liability for recommending such a procedure. I wold only add that one should use "common sense" when doing anything out of the norm with their system.

As a side note, you can use this same track to hear the reflective / all of the nodes in your room. In most installations, you'll literally hear the signal walking around the room at some points. The more that the image wanders, the more work you need in the speaker / room interphase. Sean
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I'm taking notes; thanks for the input thus far. Keep em' coming. I particularly liked the question by darrylhifi. I had not thought about possible side effects on other components, only the effects on the speakers, by using certain tracks with certain frequencies.

I have been using track 20 from stereophile test CD3. Getting a little movement in the woofers. I need to see what is really going on in that CD.