It is progressing more slowly than I thought but this recent announcement may speed up the process of personally creating an appropriate Head Related Transfer Function to allow headphones to create a realistic acoustic space. HRTF is a term used to describe how your head shape, the pinnae of your ears, your shoulders, etc allow your brain to determine positions of sounds by creating comb filtering. All those physical characteristics of your body are bypassed when using headphones contributing to the "sound in the middle of your head" syndrome. HRTF processing allows modifications of the acoustic signal to emulate your missing HRTF when using headphones. Years ago Sony had a headset controller with a rudimentary fixed HRTF correction but it had limited capability because it was not tailored to the individual. This will be interesting to follow.
https://audioxpress.com/news/psb-speake ... g-profiles