Yes, speaker "break-in", to the extent that it's sometimes claimed to exist is largely nonsense. Periods of use requiring weeks or even months are promoted occasionally and it's been said that "break-in was invented so that we couldn't return anything"! An initial permanent break-in which would take no more than a minute or so(and often would take place in factory testing before being shipped)would show a measurable "loosening" of the driver. Every time a speaker is turned off it partially reverts over a period toward its unused state, but this immediately returns to the "broken-in" state a second or so after being turned on again.
Dr. Toole and others point out the lack of any long term audible changes(in blind listening tests)which can be observed. This may be fortunate. I now have about 30,000 hours on my M22s and if some long-term changes were occurring they certainly would have reached the optimum point long ago and now would be well into a period of deteriorating performance. Instead they continue to sound identically excellent as they did when I fired them up with "The Planets" when first received.
