Here's a couple of good reads: Analog Days - The invention and impact of the Moog synthesizer, by Trever Pinch and Frank Trocco. This is a history of the development of the music synthesiser. The subtitle is a little misleading, as ARP, Buchla, EMS get detailed coverage, but as the book identifies, the winner was Moog. The other book (just out) is Blue Smoke by Chris Bourke, and is the history of New Zealand pop music from 1918 to 1964. This nicely completes the picture, bringing us up to where other texts take over (eg Stranded in Paradise).