Originally Posted by jmichaelf
There is a sensitivity rating for speakers (which is technically different from efficiency but the two are interchangeable in layspeak). You send 2.83 volts at some frequency or range of frequencies and whatever comes out is how you measure sensitivity. The louder a speaker plays at 2.83 volts, the higher sensitivity it is. This means less amplification is required and dynamic compression resulting in distortion is less likely.
Originally Posted by Djoel
He can look at the spec sheets too can't he
You're going to make him buy a fancy calculator, and some electrician test gear
More to it than that. All of the specs that I list below actually can have the same sensitivity. 2.83 volts @ 8 ohms is one watt.
8 ohm speaker, 88db 1 watt/1 meter (measured in room)
6 ohm speaker, 89.5db 2.83 volts/ 1 meter (measured in room)
4 ohm speaker, 91db 2.83 volts/1 meter (measured in room)
8 ohm speaker, 84db 1 watt/1 meter (measured in Anechoic chamber)
6 ohm speaker, 85.5db 2.83 volts/ 1 meter (measured in Anechoic chamber)
4 ohm speaker, 87db 2.83 volts/1 meter (measured in Anechoic chamber)
So looking at the above we have sensitivity measurements from 84db to 91db and yet they are the same. This is a huge difference when you consider that it takes double the power to increase 3db. I have seen speakers measured in more methods than I listed above. I have seen them measured in pairs in room and I have seen them measured in room in a corner. Both of those methods artificially inflate the sensitivity measurement. If the method of measurement does not tell you how the speaker/speakers were measured, you really do not know a whole lot.
OPer, the Heresy suggestion above is a good suggestion. Very musical speaker that can do the dynamics of HT. If you have any questions or wish to discuss farther, shoot us an email.