A minor 7th flat 5th chord on bass (Am7♭5)

Why it sounds like that

A minor 7th flat 5th is built from the formula 1, ♭3, ♭5, ♭7. The diminished 5th between A and E♭ gives the chord its tense, unresolved quality. Raising the ♭5 to a perfect 5th produces A minor 7th, the closest stable contrast.

What goes wrong with A minor 7th flat 5th?

• Letting the pinky collapse and mute the 2nd string.
• Fretting the 1st string with the ring finger too far from the fret, causing a buzz.
• Allowing the index finger to touch the 3rd string and deaden the A.

When to use it

A minor 7th flat 5th functions as the ii chord in G natural minor and the vii chord in B♭ major. Use it in minor-key jazz and blues lines where the half-diminished colour leads to a dominant. It pairs naturally with A minor and A 5th.

Changing to and from A minor 7th flat 5th

• Sliding the shape down two frets to the 3rd fret gives G minor 7th flat 5th.
• Sliding the shape up one fret to the 6th fret gives B♭ minor 7th flat 5th.

Which voicing to use

The 5th-fret root position keeps A in the bass for a grounded sound. The Am7♭5/E♭ inversion at the 11th fret places the diminished 5th in the bass, creating a darker, less stable feel. Choose the Am7♭5/G inversion when the bass line needs to descend to G.