How long it take to run in brand new loudspeaker?

My experience was the same as Bufus and I have found that a few hundred hours are needed before reaching steady-state sound no matter what low number the manufacturer gives for break-in. You may just have bought what are laid back speakers to your ears. Arthur

Aren't there two issues here? Maybe some tweeters have flexible surrounds, and thus will increase in output (get brighter) with breakin; likewise, and more commonly, woofers and mids surrounds and spiders nead to flex a LOT to break in, thereby FILLING IN the bottom. Maybe some do BOTH, widening the "shoulders" spectrally, as it were?

About 500 to 1000 hours. But of course, the speakers will continue to sound better and better until they break.

For me it has always been the bass to clear up last.My Aerial cc3 sounded like there was a comforter over it for 3 days,or more. I actually put one on it and ran it loud for 4days continuously. Then there is the Korus. A dealer in a phone conversation, said this speaker improves till it has 3,000 hrs on it.

Depends a lot on the system, of course. The Paradigm 100s in my HT set up needed 300 hours to settle in. OTOH, the Mezzo Utopias in my music room didn't change much from day one.

will