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Why? That's just what I wrote: "and of course the length and shape of your ear canal [...] (resonances!)"
No. No I don't notice the resemblance. Loudness is psychological. Sure there are similarities but the way somebody feels about how loud a pure tone is has nothing to do with dummy head measurements per se.
That's also why I keep telling those who try to EQ their headphones by equal loudness contours that that doesn't make sense.
And you stated the primary cause of the resonance as the bowl shape of the pinnae, and your wording left the effect of your ear canal ambiguous (What role? What resonances? You don't specifically say the 3 kHz resonance.): "The boost at ~3 kHz is due to the bowl-shaped part of the pinna and of course the length and shape of your ear canal also plays an important role (resonances!)."
No similarities, eh? I matched the scales, although without knowing what level the HRTF was done at I can't match to the exact ELC. They're not from the same source or even the same quarter century, so I don't know the relative accuracy. Obviously the relative sensitivity of our middle ear, inner ear, or brain (you state explicitly that it is psychological only, but I know of no evidence to that - I'd be interested in seeing it) varies with loudness, but the ELC as a derivative of the HRTF is clear. Actually, I did of course forget about the changing ELC with level - so the ELC is really the HRTF plus the inner ear transfer function (which varies by frequency rolling off in the extremes) and the level transfer function (whether it is our middle ear, inner ear, or brain isn't really relative, all that is relative is that it's not an integral part of the outer ear and thus does not vary from near source to far source or by angle of incidence).
So in the end I suppose you are really correct, however, because it's really the difference in HRTF from real life versus headphones that we want - not the frequency extreme rolloffs (beyond those in the HRTF) or the varying relative perception of frequencies at different overall levels. If you did mimic the total transfer function, you'd be doubling up on the transfer function of the middle/inner ear and brain. Problem is that it's not really easy to find your own HRTF without taking a mold of your own head, body, and all objects around you...
Now, if you can completely map the HRTF from all angles and distances, you can take any source and perform the relevant frequency response and phase change operations to map that source to mimic any other to a certain degree (less so for simulating headphones with loudspeakers, for example, when you have lots of reflections to deal with). But the opposite works very well - it's exactly what the Smyth Realiser does. Well, it only maps a single setup at a time, but it's the same principle.
