Space plays and stops
- Notes and intervals
- GbM3Bb2DbbM3Fb
- Extends
- Gb Dominant 7
Gb Dominant b5, written Gb7b5, is built from Gb, Bb, Dbb and Fb: the root, major 3rd, flat 5th and minor 7th.
Its 3rd and 7th, Bb and Fb, are its guide tones: they say what kind of chord it is, so voicings are built around them and the root is often left to the bass. C7, a tritone away, has the same two notes the other way up, so it can stand in for Gb7b5 as its tritone substitute.