Turnarounds are a section of two or four bars at the end of a tune. Their role is to create a harmonic transition going back to the beginning. They are present in many jazz tunes and are an important part of "rhythm changes" progressions. They are also used to create effective jazz intros and endings.
This lesson with guitar tabs contains 17 exercises to gain a better understanding of the I VI II V variations.
One of the most popular jazz chord substitution is the tritone substitution sometimes referred to as dominant chord substitution.
It consists in replacing a dom7 chord by another dominant 7th chord whose root is a tritone away from this initial chord. Example with G7 (V), which can be replaced by Db7 which is a tritone (three whole-steps) away from G7
Thus giving two chords that have two notes in common. The 7th of G7 (F) is the third of Db7 and the third of G7 (B) is the seventh of Db7. The inversion of the 3rds and the 7ths between the original dominant chord (V) and the substituted dominant chord (bII7) is the main feature of the tritone substitution.
1- Blues progressions and variations
2- Chord studies
3- Guitar walking-bass studies
4 -Rhythm patterns