Phusis and Duke, I beg to agree and disagree. I have always said the more power the better. This is a relative statement, relative to efficiency and other factors such as the output capability of the speaker. A speaker can only do so loud.
I have been listening to as many horn loaded loudspeakers as I can lately and in general they are very impressive or can be very impressive. It is certainly easier to get dynamic sound because they are so efficient and they go very loud. Now an ESLs volume capability is based on its Xmax which is very small in comparison to dynamic speakers. If you try to run it full range with bass laden material it will run out of Xmax pretty quickly and start clipping or rapping the stators. However if you do two things the situation turns upside down. These are, send everything under 100 Hz to a subwoofer array and design the speaker so that it is a full range line source. What you get is every bit as dynamic as a horn system and I think because there are no crossovers otherwise, an effortless naturalness that makes the speakers disappear. Line sources project power better than point sources. Because ESL almost match the impedance of air their transfer of power is very efficient even if their electrical efficiency is not. So, you have a very dynamic, low efficiency speaker system that goes very loud and has no crossovers above 100 Hz.
Phusis, lets say you have two speakers that both clip at 120 dB at 1 meter. One has an efficiency of 103 dB/1watt/meter and the other 84dB/1watt/1 meter. With a paltry 2 watts the first is blasting at 106 dB and the second only at 87db. To get the second to 106 dB you need 160 watts and this is at 1 meter. At a reasonable listening distance you are easily under 100db, probably down towards 95 dB. We are not even talking about peaks here. The point is that low efficiency speakers require a lot more power to hit dynamic peaks, hundreds of watts. Duke, your friend has more work to do. There are so many factors involved that I doubt you can make a blanket statement that high efficiency speakers are all more dynamic than low efficiency speakers of various types given appropriate power. It is certainly easier to make high efficiency speakers sound dynamic and I would rather have a good sounding high efficiency loud speaker than an equally good sounding low efficiency speaker. The more power on a relative basis the better. Fortunately for me ESLs are more efficient than ever 89-90dB/1watt/meter and there are plenty of amps now that can drive them without farting or blowing up. I should be able to hit 100 dB without leaving Class A operation.
I have been listening to as many horn loaded loudspeakers as I can lately and in general they are very impressive or can be very impressive. It is certainly easier to get dynamic sound because they are so efficient and they go very loud. Now an ESLs volume capability is based on its Xmax which is very small in comparison to dynamic speakers. If you try to run it full range with bass laden material it will run out of Xmax pretty quickly and start clipping or rapping the stators. However if you do two things the situation turns upside down. These are, send everything under 100 Hz to a subwoofer array and design the speaker so that it is a full range line source. What you get is every bit as dynamic as a horn system and I think because there are no crossovers otherwise, an effortless naturalness that makes the speakers disappear. Line sources project power better than point sources. Because ESL almost match the impedance of air their transfer of power is very efficient even if their electrical efficiency is not. So, you have a very dynamic, low efficiency speaker system that goes very loud and has no crossovers above 100 Hz.
Phusis, lets say you have two speakers that both clip at 120 dB at 1 meter. One has an efficiency of 103 dB/1watt/meter and the other 84dB/1watt/1 meter. With a paltry 2 watts the first is blasting at 106 dB and the second only at 87db. To get the second to 106 dB you need 160 watts and this is at 1 meter. At a reasonable listening distance you are easily under 100db, probably down towards 95 dB. We are not even talking about peaks here. The point is that low efficiency speakers require a lot more power to hit dynamic peaks, hundreds of watts. Duke, your friend has more work to do. There are so many factors involved that I doubt you can make a blanket statement that high efficiency speakers are all more dynamic than low efficiency speakers of various types given appropriate power. It is certainly easier to make high efficiency speakers sound dynamic and I would rather have a good sounding high efficiency loud speaker than an equally good sounding low efficiency speaker. The more power on a relative basis the better. Fortunately for me ESLs are more efficient than ever 89-90dB/1watt/meter and there are plenty of amps now that can drive them without farting or blowing up. I should be able to hit 100 dB without leaving Class A operation.