Athmasphere, I have a question for you.
First, background: In this discussions most of participants when refer to impedance mean only its modulus.
from Simon Thacher of Spectron paper
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... loudspeaker loads comprise complex impedances with both resistive and reactive (capacitive and inductive) components. Such impedance can be depicted as a vector with its magnitude (modulus) and angle (phase), and both vary with frequency. In general, the voltage and current waveforms, in complex impedance load, are out of phase with each other and therefore, to characterize accurately a speaker's load impedance, both modulus vs frequency and phase vs frequency plots must be known. Frequently, the phase angle is much more crucial to the speaker load than the modulus alone
To deal with this phenomenon, Keith Howard ("How Much Power Do I Need?" Hi Fi News July-Sept, Nov 2007 ) introduced the figure of merit he has labeled Equivalent Peak Dissipation Resistance (EPDR). This is, simply, the resistive load that would give rise to the same peak power device dissipation as the speaker itself. Using EPDR as a figure of merit, the speakers can be compared directly with each other.
Sorry for tbe long introduction: Question is simple: do you agree with Keith Howard figure of merit (EPDR) and if so why speaker manufacturers are not utilizing it, and amplifier manufacturers are not demanding it?
Thank you.