Appreciate the reply on this, GoldenSound. And your invitation to get more involved in discussions of measurements.
Things are different. But they’re also sort of the same, according to the folks at Harman and their research. Speakers will of course measure differently in a room than they do in the ear of a mannikin. And you can look at and consider both their on and off-axis responses in assessing them, which is something you can’t really do with most or all headphones.
Still, in interviews, conferences, promos, etc., the folks at Harman (like Dr. Olive) are much more apt to stress the strong parallels and throughlines in their research on loudspeakers and headphones. And the parallel between the in-ear response of neutral speakers in a semi-reflective room and the preferred in-ear response of headphones that they found in their research. I’ve posted a couple examples of this below for your and others perusal.
According to Dr. Olive, roughly a 2/3 majority of the listeners in their early studies preferred an in-ear response in headphones close to the in-ear measured response of speakers in a semi-reflective room. The remaining 1/3 also preferred the same type of response with a little more or less bass or treble, depending on their age, testosterone levels, and hearing loss.
Another video featuring Dr. Olive and Omid Khonsaripour of Harman that draws comparisons between headphones based on their target and the in-ear sound of speakers in a room.
