Major Blues scale in 12 keys (C, C# Db, D, D# Eb, E, F, F# Gb, G, G# Ab, A, A# Bb, B) for bass 5-string. Diagrams in all keys with fingerings, note names, intervals. Relation scale to chords and formula. Tabs in the key of C with audio tracks. Backing-tracks in various keys and drum beats.