F7♭5
F 7th Flat 5 · 4 fingerings
Flatten the fifth of a dominant seventh and F7♭5 becomes considerably more unstable and modern-sounding. It's a jazz and fusion colour, usually functioning as a substitute dominant on its way to resolution, and it pairs well with whole-tone and altered scale ideas. Uncommon outside of jazz, but striking when it lands.
F7♭5 · position 1
F7♭5 · position 2 · fret 3
F7♭5 · position 3 · fret 6
F7♭5 · position 4 · fret 8