10-01-12: Rower30I had indicated that the average SPL of the recordings I referred to were "perhaps in the low 70's." I doubt that anyone would want to play them at an average level of 85 db, with peaks of 115-120 db. That is simply too loud. As a point of reference, as noted in this thread 8 hours is the limit of permissible continuous exposure to 85 db, beyond which hearing damage can be expected to occur.
The dynamic range reference is from the AVERAGE SPL, not the minimum. So if your avevrage SPL is 85dB, your peak dynamic range will be 115dB, not a value most systems can manage.
Some of that precious little energy is wasted as heat as you say, but the majority is imaginary in vector.What do you base that on?
That would say that a speaker whose impedance has small phase angles across the audible frequency range would approach 100% efficiency. My understanding is that most speakers do not have as much as 10% efficiency. You cited a figure of 5%. And it is rare for a speaker to have phase angles that exceed or even approach 45 degrees across broad parts of the spectrum (although that can occur across narrow ranges of frequencies). Meaning that their impedance is mostly resistive. That can be seen in the measurements that are provided by John Atkinson in Stereophile's speaker reviews.
As an additional point of reference, note in this Wikipedia writeup that the acoustic power radiated by a jackhammer is all of about 1 watt! If the 50 or 100 electrical watts or thereabouts that may be sent into a speaker at times were reduced to that kind of acoustic power level (or less) primarily as a result of non-resistive impedance characteristics (as opposed to conversion to heat), it would say that the impedance would have to be almost entirely either inductive or capacitive (i.e., having phase angles approaching +90 or -90 degrees) across nearly the entire frequency range. Which, frankly, is nonsensical, as well as being completely inconsistent with JA's measurements.
Kijanki, LOL :-)
Regards,
-- Al