This book and Cd combo is all about Om, the most fundamental and ancient of the yogic mantras. In the book we learn the origin, symbolism and effects of both the Om mantra and its graphic representation, the Sri Yantra. The book also goes into detail on the yogic practices to use Om for meditation and contemplation, many which incorporate the musical tracks on the Cd. Oms of different pitches and harmonic overtones are either sung solo, in triads, or choruses and fill the entire 74-minute Cd. These tracks can be used in multiple ways, from passive listening to accompanying the exercises and meditations explained in the book.