5
Fig. 1 — nothing to hold

guitar chord

B♭5

B♭1F5

Root and fifth, no third at all — neither major nor minor, which is the point.

Written the other way round it is A♯5 — the same twelve keys on a piano, a different piece of notation.

on ukuleleon pianothe scale

What is true of it

B♭5 is B♭ and F — 1 and 5 counted from B♭.

No fingering of B♭5 fits a hand on the guitar: inside four frets, with the strings that sound next to each other and the root underneath, there is nothing to hold.

Where its notes are on the neck

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Fig. 2 — first 12 frets

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

With a different note underneath

first inversion

B♭5/F

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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.

B♭ in other shapes

B♭majorB♭mminorB♭dimdiminished

C5C♯5D♭5D5D♯5E♭5E5F5all 374