To a large extent there is no direct relationship. Some of the better speakers have low sensitivity and therefore require high power, high current amplifiers. When properly driven these speakers sound super. OTOH, many high sensitivity speakers have low mass driver elements. Less mass, less inertia -- the speaker cone should be able to respond more quickly to the music signal. Speakers designed along this principal can also sound super. My personal opinion is that it should be cheaper to design a high sensitivity speaker than a high powered amplifier. Regardless, either path works.
Speaker sensitivity?
What role does peaker sensitivity play in the musical nature of a speaker. I understand the power issue. But, this is the first time i have ever thought to ask about this aspect. My general understanding is that it doesnt neccessarily afect this but is more related to speaker cabinet and crossover construction. Please explain!!