Gb thirteenth chord
Gb13 chord for piano presented by keyboard diagrams.
Explanation: The G flat thirteenth is a seven note chord. Due to practical circumstances, some notes (as a suggestion fifth, ninth, and eleventh) is omitted and the chord is played inverted. The chord is often abbreviated as Gb13.
Theory: The Gb thirteenth chord is constructed by adding a third to an eleventh chord.
Notes: Gb - Bb - Db - E - Ab - B - Eb