Finger Positions

Root Note B

Name B diminished seventh over F#

Intervals 1P-3m-5d-7d

Relative Minor G#m

Notes F#, B, D, F, Ab

Aliases Bdim7, B°7, Bo7

How to play the Bdim7/F# Chord

The Bdim7/F# is a fundamental dominant chord in guitar music. To play this chord correctly, ensure your fingers are placed precisely on the frets indicated in the diagram above.

Music Theory Analysis

From a theoretical perspective, the B diminished seventh over F# is built using the 1P, 3m, 5d, 7d intervals. In the key of B Major, this chord functions as the I chord.

Common Progressions

In music composition, the Bdim7/F# chord is often used to create tension or resolution.

I-V-vi-IV

B → F# → G#m → E

vi-IV-I-V

G#m → E → B → F#

The Diatonic Family

Understanding the "family" of chords that belong to B helps with transposition and ear training.

Triads

B C#m D#m E F# G#m A#dim

7ths

Bmaj7 C#m7 D#m7 Emaj7 F#7 G#m7 A#m7b5

Scale Compatibility

View All Scales

Diminished Ultralocrian Locrian 6 Dorian #4 Lydian Diminished Hungarian Major Lydian #9 Half-Whole Diminished Composite Blues Messiaen's Mode #7 Chromatic

* 11 scales found containing the notes F#, B, D, F, Ab.

Acoustic & Digital Analysis

Digital footprint of the Bdim7/F# chord for MIDI programming and synthesizer sound design.

MIDI Numbers 66, 71, 62, 65, 68

Frequencies (Hz)

369.9944227116344, 493.8833012561241, 293.6647679174076, 349.2282314330039, 415.3046975799451