@larryi wrote: "I sort of think that 95-96 is at the low end of the range. My speakers are 99 db/w efficient, and friend calls that medium efficiency (his speakers are above 112 db/w efficient."
Imo this is something to be aware of:
Very often the limiting factor for high-efficiency systems is the on-axis frequency response at high frequencies. And one way to get very high efficiency numbers is to use a horn whose pattern at high frequencies is very narrow, such that all of the high frequency energy is concentrated in a narrow beam, thereby maximizing the on-axis sound pressure. If the same compression driver were used on a wide-pattern horn, the same amount of acoustic energy would come out, but because it’s spread over a wider angle the on-axis PRESSURE would be less.
By way of analogy, consider a garden hose with an adjustable nozzle. The on-axis PRESSURE is higher when the nozzle is adjusted for the narrowest possible pattern, but the same AMOUNT of water comes out regardless of the pattern width. So too with horn radiation patterns.
Implied by this is the fact that an omnidirectional speaker system is actually putting out a lot more acoustic energy than we would normally infer from its "on-axis" efficiency. So comparing efficiency (or voltage sensitivity) specs is not necessarily making an "apples to apples" comparison.
Duke
