F♯ diminished major 7th chord on bass (F♯dimMaj7)

Why it sounds like that

F♯ diminished major 7th is built from the formula 1, ♭3, ♭5, 7. The diminished 5th between F♯ and C creates a tritone that gives the chord its dark color. The major 7th E♯ is a leading tone that resolves upward to F♯. Compare with F♯ minor 7th flat 5th, which has E instead of E♯.

What goes wrong with F♯ diminished major 7th?

• Letting the ring finger mute the 2nd string, which silences the A.
• Pressing the pinky too lightly, causing the 2nd string to buzz.
• Allowing the index finger to drift sharp, making the 4th string note out of tune.

When to use it

F♯ diminished major 7th works as a passing chord in F♯ minor, often between F♯ minor and F♯ minor 7th. Its tense sound suits jazz ballads and dramatic film cues. Use it to add chromatic motion on the bass.

Changing to and from F♯ diminished major 7th

• Sliding the shape down one fret to the 1st fret gives F diminished major 7th.
• Sliding the shape up one fret to the 3rd fret gives G diminished major 7th.

Which voicing to use

The 2nd-fret position places the root F♯ on the 4th string, giving a solid low foundation. The 14th-fret shape is the same voicing an octave higher and is movable.