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I have no idea if he said it or not.
All I know is that Harman speakers (Revel, Infinty, budget JBL) have very wide dispersion characteristics, flat into the high-thousands and with very little attenuation as you move away from the axis. There's a fair chance that he is practicing what he preaches.
Hey @tuga, I'm afraid I have to walk back from what I said on this question earlier today. Have just re-read the 2004 study and indeed there are target slopes specified for the various indices that take into account off-axis radiation.
This is what Olive states by way of explanation:
"For each of the 7 frequency response curves, the overall smoothness (SM) and slope (SL) of the curve was determined by estimating the line that best fits the frequency curve over the range of 100 Hz-16 kHz....Smoothness (SM) values can range from 0 to 1, with larger values representing smoother frequency response curves."
"Target slopes were determined separately for Test One and for our larger test sample (70 loudspeakers) used for the generalized model described in section 5. The target values are based on the mean slope values of speakers that fall into the top 90 percentile based on preference ratings. Target slopes are defined for each of the 7 frequency curves (see table 2). The ideal target slope for the on-axis and listening window curves (0 and –0.2) is identical for both test samples, which indicates that the on-axis curve should be flat, while the off-axis curves should tilt gently downwards. The degree of tilt varies among curves for Test One and the larger sample. Test One includes mostly 2-way designs whereas the larger sample includes several 3-way and 4-way designs that tend to have wider dispersion (hence smaller negative target slopes) at mid and high frequencies. This suggests that the ideal target slope may depend on the loudspeaker’s directivity."
And then he provides this table:
The abbreviations correspond to "on-axis", "listening window", "early reflections", "predicted in-room", "sound power", "early reflections DI", and "sound power DI" respectively.
In other words, while stating that "the ideal target slope may depend on the loudspeaker’s directivity" (where I thought he stood), in effect his model is indirectly specifying a target beamwidth (where you thought he stood), since the beamwidth will be the primary determinant of all these target slopes other than the first two.
A.k.a, you were right and I was wrong
So thanks for bringing that to my attention.
And yeh, this is a problem with the model IMO!
TBH, I don't understand why smoothness of these curves ("SM" in his nomenclature) was not left as the only criterion, as this would be more consistent with his stated position, it seems to me.