Garner, Robert: Essential Music Theory For Electric Bass  

This book is designed to help guide a beginning music theory dialogue between instructor and student in private one-on-one lessons. Six areas of beginning music theory are covered. The major scale, the natural minor scale, intervals, triads, seventh chords and harmonized major and minor scales. Fingerings, intervallic structures and note names are also diagrammed in each chapter.

It is highly recommended that this book is used in the course of study with a professional bass instructor, though many players have found the book to be useful in self-study. A good bass teacher will help explain and demonstrate theory concepts in a live setting and also shed additional light in terms of alternate fingerings, ear training and gaining full technical mastery of theory concepts across the entire fingerboard.