Theodore Gracyk 
On Music [PDF ebook] 

Opinionated and example-filled, this extremely concise and accessible book provides a survey of some fundamental and longstanding debates about the nature of music. The central arguments and ideas of historical and contemporary philosophers are presented with the goal of making them as accessible as possible to general readers who have no background in philosophy. The emphasis is on instrumental music, but examples are drawn from many cultures as well as from Western classical, jazz, folk, and popular music.