B♭ (musical note)
B♭ (B-flat; also called si bémol) is the eleventh step of the Western chromatic scale (starting from C). It lies a diatonic semitone above A and a chromatic semitone below B, thus being enharmonic to A♯, even though in some musical tunings, B♭ will have a different sounding pitch than A♯. B-flat is also enharmonic to C.
When calculated in equal temperament with a reference of A above middle C as 440 Hz, the frequency of the B♭ above middle C is approximately 466.164 Hz. See pitch (music) for a discussion of historical variations in frequency.
While orchestras tune to an A provided by the oboist, wind ensembles usually tune to a B-flat provided by a tuba, horn, or clarinet.
In Germany, Russia, Poland and Scandinavia, this pitch is designated B, with 'H' used to designate the B-natural. Since the 1990s, B-flat is often denoted Bb or "Bess" instead of B in Swedish music textbooks. Natural B is called B by Swedish jazz and pop musicians, but still denoted H in classical music. See B (musical note) and Musical note: Note names and their history for explanations.
Designation by octave
Scientific designation | Helmholtz designation | Octave name | Frequency (Hz) |
---|---|---|---|
B♭−1 | B♭͵͵͵ or ͵͵͵B♭ or BBBB♭ | Subsubcontra | 14.568 |
B♭0 | B♭͵͵ or ͵͵B♭ or BBB♭ | Subcontra | 29.135 |
B♭1 | B♭͵ or ͵B♭ or BB♭ | Contra | 58.27 |
B♭2 | B♭ | Great | 116.541 |
B♭3 | b♭ | Small | 233.082 |
B♭4 | b♭′ | One-lined | 466.164 |
B♭5 | b♭′′ | Two-lined | 932.328 |
B♭6 | b♭′′′ | Three-lined | 1864.655 |
B♭7 | b♭′′′′ | Four-lined | 3729.31 |
B♭8 | b♭′′′′′ | Five-lined | 7458.62 |
B♭9 | b♭′′′′′′ | Six-lined | 14917.24 |
B♭10 | b♭′′′′′′′ | Seven-lined | 29834.481 |
Scales
Common scales beginning on B♭
- B-flat major: B♭ C D E♭ F G A B♭
- B-flat natural minor: B♭ C D♭ E♭ F G♭ A♭ B♭
- B-flat harmonic minor: B♭ C D♭ E♭ F G♭ A B♭
- B-flat melodic minor ascending: B♭ C D♭ E♭ F G A B♭
- B-flat melodic minor descending: B♭ A♭ G♭ F E♭ D♭ C B♭
Jazz melodic minor
- B♭ ascending melodic minor: B♭ C D♭ E♭ F G A B♭
- B♭ Dorian ♭2: B♭ C♭ D♭ E♭ F G A♭ B♭
- B♭ Lydian augmented: B♭ C D E F♯ G A B♭
- B♭ Lydian dominant: B♭ C D E F G A♭ B♭
- B♭ Mixolydian ♭6: B♭ C D E♭ F G♭ A♭ B♭
- B♭ Locrian ♮2: B♭ C D♭ E♭ F♭ G♭ A♭ B♭
- B♭ altered: B♭ C♭ D♭ E F♭ G♭ A♭ B♭
See also
- Piano key frequencies
- Category:B-flat instruments
- B-flat major
- B-flat minor
- Root (chord)