hispls
5,000+ posts
CarAudio.com Veteran
That whole "break in" is just a boogeyman used by companies to weasel out of warranty claims. If your sub is breaking mechanically it was built wrong to begin with or you are abusing it and it would have broken no matter how long you played it at lower power first. Again, my experience is that the dramatic shift in TS parameters happens in like a half hour of hard play. Guys who get their best number with fresh (stiff) softparts will rebuild subs right before a big competition. Think about how little play time that is at 3 seconds twice even if they compete every weekend!
20-30% change in FS and Qms happens really quickly, after that, particularly with "competition" type subs (with very stiff suspension) you won't get much more ever. It's not like the old days where cloth spiders would soften to the point where they'd visibly sag if you mounted them facing up over enough time. Modern spider stiffness and materials simply won't allow that to ever happen. Oh, and from the couple that Ive measured then plugged in specs the 20-30% shift in those specs results in very little actual change in predicted response. Much of the actual "difference" you hear MUST be psycho semantic just getting used to the new sound or finding different "favorite" songs that sound best. If you have some modeling software I'll post some specs of one that I saved and you can see for yourself what to really expect.
