Buying Speakers: A Speaker Designer’s Perspective

Whilst surfing over at AVS Forum, looking for information on
Small/Large setup for our HT Basics feature, I noticed a great thread
talking about speaker design and the role they have getting the music
to your ears. As mentioned in the title, this is from a designer's
perspective and should shed a lot of light on how different components
in your HT work together.

From AVS Forum:

It is a commonly held belief that speakers are the most important part
of a stereo system, or home theater. This is basically true, though not
to the extent that many experts would have you believe. The speakers
control how much of the music you hear. By that I mean they will
usually be the limiting factor in terms of how deep the bass is, how
extended the treble is, and the overall amount of detail that is
allowed to pass through. In other words, speakers determine the outside
edges of the performance envelope, and the other components determine
how far you fill that envelope.