Quote Originally Posted by bcdon View Post
What is the purpose of this 'break-in' ? Are all speakers broke-in is some fashion or another (e.g. stereo speakers, tv speakers, &c)?
The break in loosens up the parts. The consensus is that speakers sound better after being broken in. Some speakers can sound shrill and "stiff" and breaking them in can tame the ragged high end. This article explains it better than I can:

http://www.premierguitar.com/Magazin..._Speakers.aspx

Stereo speakers are a different animal. They have synthetic cones and surrounds, which do not loosen up over time like the paper cones in guitar speakers. Stereo speakers are typically played clean with no distortion in the signal, their purpose is to reproduce recorded sound. Guitar speakers generate music and there can be lots of harmonic distortion in the signal.