Why low sensitivity speakers?

Gs5556, I guess it's how you look at it. The people designing speakers with a high sensitivity don't have "limited bass response" as a design goal, just like people designing a speaker with good bass response don't have "low sensitivity" as a design goal.

I like your analogy, which makes since, but what physically makes this true is not obvious. I guess that with a given driver, and enclosure, it is through low "acoustic compliance" that lower frequencies response is attained.

Karls, just saw your last comment. Good point. It is the "suspension compliance" along with the "acoustic compliance" that results in the lower resonance of the system. I think we've got it figured out!

Perhaps my explaination was not clear. It is not the driver response, but rather the crossover that makes the efficiency (thus sensitivity) change. Gs556 analogy is really excelent and as to how it applies to speakers, it's back to what I said in the beginning. Lower frequencies require more movement of air to achieve the same SPL, thus they are the "heavier bottles". Great analogy Gs5556.

In response to bass: a stiffer cone (woofer) is required to produce a 'tight' bass. a cone that is less stiff will deform, causing muddy, poorly reproduced bass. the tradeoff here is that the stiffer cone requires more power (is less efficient).

Great explanation, Karls.