[cyrano]

I'm - very slowly - learning that the mics are the problem. Only the Core Sound Mic (and maybe the Zylia and the Brahma) offers full calibration. And recalibration in a few years. The others chose a "general" calibration, eg, not for the individual capsules and no recalibration.

Second problem is HRTF. I've read somewhere this could boil down to 7 basic head types. But I haven't seen these 7 types anywhere, so I'm taking that with a grain of salt. There was talk of an online HRTF calculation service, but I don't know where that's at. It should be possible starting from a precise series of pictures.