×A#EGC#E
Fig. 1 · A#dim7 · open

guitar chord

A♯dim7

A♯1C♯♭3E♭5G♭♭7

Three minor thirds stacked. The seventh is doubly diminished, which is why it is written with a double flat.

Written the other way round it is B♭dim7 — the same twelve keys on a piano, a different piece of notation.

on ukuleleon pianothe scale

Every fingering that fits a hand

Fig. 2

x12020

open

Fig. 3

645050

moderate

Fig. 4

x1202x

open

Fig. 5

x12023

moderate

Fig. 6

64505x

hard

What is true of it

A♯dim7 is A♯, C♯, E and G — 1, b3, b5 and bb7 counted from A♯.

The easiest of the 5 fingerings below is x12020: 3 fingers, held at the 1st fret.

2 of them use open strings, which is what makes a shape quiet to change to.

1 string stays silent.

Where its notes are on the neck

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Fig. 7 — first 12 frets

The brass dots are A♯, the root. Everything else is a chord tone with its degree printed in it.

With a different note underneath

first inversion

A♯dim7/C♯

x45350

second inversion

A♯dim7/E

012020

third inversion

A♯dim7/G

312020

An inversion is the same chord with a different note lowest. The name changes to a slash name because the bass is what a listener hears as the foundation.

A♯ in other shapes

A♯7dominant seventhA♯maj7major seventhA♯m7minor seventhA♯majorA♯mminorA♯dimdiminished

Cdim7C♯dim7D♭dim7Ddim7D♯dim7E♭dim7Edim7Fdim7all 374