Interesting, but feels very incomplete, and the choice of subject for the chapters seems somewhat arbitrary once past the initial sections on the history of listening and recording technologies. There are whole fields of knowledge that go mostly unmentioned - architectural acoustics, cinema surround sound, video game ambisonics - these are not the focus of the book but all contribute to a listening subject's perception of their sonic-spatial world, and the book would be stronger if these were connected to the history and other examples here. Additionally, the war thread is left dangling - why not expand on how sensing technologies influenced experimental musicians, for example in how military surplus radio parts, oscillator circuits, etc were repurposed by early electronic artists, who also dealt with spatial audio installations? Such a short book must limit its scope, but I was left feeling a lot was missing.