An altered chord is a chord containing one (or several) altered notes that don't belong to the diatonic scale. These notes are the b5 (flat fifth), #5 (sharp fifth), b9 (flat ninth), #9 (sharp ninth). In other words, altered chords are diatonic chords where the fifth and/or the ninth have been lowered or raised by one semitone.
In this guitar lesson we will see that they can be grouped into three disctinct families that are (major, minor and dominant) and also how to play them on guitar.
Altered chords are a very important part of jazz language, they are built by altering with a flat or a sharp one or more notes of a diatonic chord. They are very useful to bring a little bit of tension to any jazz chord progression.
This lesson focusses on dominant seventh flat fifth chords (7b5), that are dominant seventh chords with a lowered fifth, given the formula : root (R), third (3), flat fifth (b5) and minor seventh (b7).
Seventh chords (aka four-note chords) represent the backbone of jazz harmony. It is common to extend them with extra tones. These other notes form the upper structure of a chord which includes the 9th, 11th and 13th.
Adding extensions to chords help to get off the beaten tracks and provides some new harmonic colors to your playing (chord soloing, comping, and arrangement).
This lesson provides useful extended major 7th chord shapes to apply to your playing.