Philosophers of music go to great lengths in attempting to explain music philosophically. This says something about the great depths of music. I suspect that the complexity of these books comes about because the philosophy of music is really a philosophy of the mind, and not a philosophy of notes. Music taps into all areas of the mind, down to the most basic areas, dealing with the physical world.
In this book, Roger Scruton is not shy about using the full force of technical terminology about both music and philosophy. He moves quickly from idea to idea and nimbly covers his subjects.
Scruton emphasizes the wholistic nature of music. Music is at once technical and emotional. Form and content are inseparable. The composition itself and the performance itself work together.
The book is divided into two parts. Part I is called "Aesthetics." Part II is called "Criticism." I found part I to be quite interesting and often convincing. Part II did not hold my attention. Part II is full of superlatives and gushing praise and harsh condemnations.
I have to admit I liked the final chapter, an extended criticism of Adorno. I have always found Adorno's writing on music to be bizarre at best.