JSD Sound Design
Speaker sensitivity is a specification provided by all manufacturers of high-quality speakers. The sensitivity rating has no relation to sound quality, as some of the very best speakers have low ratings. Sensitivity ratings simply tell you how much sound a speaker will produce for a given power input.
Sensitivity ratings are given in decibels per watt at one meter, or db/Wm. So, with an input of one watt (usually white noise), a speaker with a sensitivity of 90 db/Wm will produce 90 decibels of sound at a distance of one meter. A sensitivity of 90 is considered average, with ratings of 87 and below considered low sensitivity and above 93 considered high sensitivity. To increase the volume by 3 db, you must double the power. So, using the example above, to make 93 db you would need two watts, and to make 96 decibels, four watts.