Scott. Welcome to the forums. Most people seem to be happy with an approximation of the real thing, so thats what many manufacturers make. Its always about tradeoffs.
The issues of good sound reproduction have been covered well by previous posts. Speaker design for accurate sound is well known: ruler flat on and off axis without distortion. If you look at speaker manufacturers that follow this design philosophy, you will be on your way. B&W, Axiom, Paradigm, Energy and PSB are a few that come to mind.
