Katz has a formal background in musicology, which means basically, extensive training in the history of western classical music.
Though the language and tone of the book is meant to avoid academic linguistic density, this paradigm (of classical music) is strongly evident in his methods, pacing, argument structures, and conclusions.
Sadly, there is absolutely no attempt at an ethno/socio/anthropo-logical approach in the book. So Katz is taking a background in classical melodic & harmonic & structural theory and history, and then applying it to a phenomenon (recorded sound) that has become inextricably wound up in SOCIAL factors of the day. How people share music is less purely musical phenomenon and much more largely a social one. Katz does not successfully convey the growing wealth of thought surrounding these studies.
By focusing solely on music in the recorded medium, he ignores the forest for the tree: what is happening with newspapers, videos, movies, books, theater, poety -- in other words, ALL MEDIA are undergoing transformation. To take an arbitrary slice out of this dense network of practices and consumer/audience expectations is a very difficult task, and I don't feel it's done successfully, here.
The overall form is a loose chronological history, which falls prey to the danger of technological determinism, that one scenario led to the next, inventions directly resulting in practices, and so on, until we got to where we are today. Katz chooses not to confront the paradigm shift of decentralized communications and media distribution. It's all about a progression of distribution media and their physical properties.
Also, very little consideration was given to the idea of authorship, intellectual property, sampling as an artistic vs. reproductive art, etc. The ideas are passed-over during a discussion of sampling, but not elaborated.
Where Katz succeeds is in his realm of expertise: classical music. His treatment of records and violin vibrato and Hindemith's grammophone music are well executed reflections of those particular moments of history. But in ignoring huge areas of communications studies and giving an extremely weak treatment of hip hop, Katz shadows these achievements.
Katz' colorful description of a DJ battle, described in fantastical imagery, are absolutely cringe-inducing to me, personally. Given the well-acknowledged dangers of exoticism and neo-colonialism in ethnographic work, Katz is remiss for slipping into a language that could be taken as a neo-colonial musicological expedition. It is quite telling that he lists no references to Steven Feld's work. This chapter prompts me to imagine a photograph of him posing, one knee hiked up, on a speaker cabinet, holding his jungle-explorer's helmet against his waist, so proud of the discovery he is about to share with the world: the DJ....