A♯ (musical note)

A♯ (A-sharp), or la dièse, is the eleventh semitone of the solfege. In some countries (where B is known as H) it is informally called B.

This note lies a chromatic semitone above A and a diatonic semitone below B, thus being enharmonic to si bémol or B♭ (B-flat).

When calculated in equal temperament with a reference of Aabove middle C as 440 Hz, the frequency of the A♯ above middle C is approximately 466.164 Hz. See pitch (music) for a discussion of historical variations in frequency.

Designation by octave

Scientificdesignation	Helmholtzdesignation	Octave name	Frequency (Hz)
A♯−1	A♯͵͵͵ or ͵͵͵A♯ or AAAA♯	Subsubcontra	14.568
A♯0	A♯͵͵ or ͵͵A♯ or AAA♯	Subcontra	29.135
A♯1	A♯͵ or ͵A♯ or AA♯	Contra	58.270
A♯2	A♯	Great	116.541
A♯3	a♯	Small	233.082
A♯4	a♯′	One-lined	466.164
A♯5	a♯′′	Two-lined	932.328
A♯6	a♯′′′	Three-lined	1864.655
A♯7	a♯′′′′	Four-lined	3729.310
A♯8	a♯′′′′′	Five-lined	7458.620
A♯9	a♯′′′′′′	Six-lined	14917.240
A♯10	a♯′′′′′′′	Seven-lined	29834.481

Scales

Common scales beginning on A♯

• A♯ Major: A♯ B♯ C  D♯ E♯F  G  A♯
• A♯ Natural Minor: A♯ B♯ C♯D♯ E♯ F♯ G♯ A♯
• A♯ Harmonic Minor: A♯ B♯C♯ D♯ E♯ F♯ G  A♯
• A♯ Melodic Minor Ascending: A♯ B♯ C♯ D♯ E♯ F  G A♯
• A♯ Melodic Minor Descending: A♯ G♯ F♯ E♯ D♯ C♯ B♯A♯

Diatonic scales

• A♯ Ionian: A♯ B♯ C  D♯ E♯F  G  A♯
• A♯ Dorian: A♯ B♯ C♯ D♯E♯ F  G♯ A♯
• A♯ Phrygian: A♯ B C♯ D♯E♯ F♯ G♯ A♯
• A♯ Lydian: A♯ B♯ C  D  E♯F  G  A♯
• A♯ Mixolydian: A♯ B♯ C D♯ E♯ F  G♯ A♯
• A♯ Aeolian: A♯ B♯ C♯ D♯E♯ F♯ G♯ A♯
• A♯ Locrian: A♯ B C♯ D♯ E F♯ G♯ A♯

Jazz melodic minor

• A♯ Ascending Melodic Minor: A♯ B♯ C♯ D♯ E♯ F  G A♯
• A♯ Dorian ♭2: A♯ B C♯ D♯E♯ F  G♯ A♯
• A♯ Lydian Augmented: A♯ B♯C  D  E  F  G  A♯
• A♯ Lydian Dominant: A♯ B♯ C D  E♯ F  G♯ A♯
• A♯ Mixolydian ♭6: A♯ B♯ C D♯ E♯ F♯ G♯ A♯
• A♯ Locrian ♮2: A♯ B♯ C♯D♯ E F♯ G♯ A♯
• A♯ Altered: A♯ B C♯ D E F♯G♯ A♯

B (musical note)

B, also known as Si, Ti,

or, in some European countries, H, is the seventh note of the fixed-Do solfège. Its enharmonic equivalents are C♭ and A  .

When calculated in equal temperament with a reference of Aabove middle C as 440 Hz, the frequency of Middle B (B₄) is approximately 493.883 Hz. See pitch (music) for a discussion of historical variations in frequency.

Designation by octave

Scientificdesignation	Helmholtzdesignation	Octave name	Frequency (Hz)
B−1	B͵͵͵ or ͵͵͵B or BBBB	Subsubcontra	15.434
B0	B͵͵ or ͵͵B or BBB	Subcontra	30.868
B1	B͵ or ͵B or BB	Contra	61.735
B2	B	Great	123.471
B3	b	Small	246.942
B4	b′	One-lined	493.883
B5	b′′	Two-lined	987.767
B6	b′′′	Three-lined	1,975.533
B7	b′′′′	Four-lined	3,951.066
B8	b′′′′′	Five-lined	7,902.133
B9	b′′′′′′	Six-lined	15804.266
B10	b′′′′′′′	Seven-lined	31608.532

Scales

Common scales beginning on B

• B major: B C♯ D♯ E F♯ G♯A♯ B
• B natural minor: B C♯ D E F♯ G A B
• B Harmonic minor: B C♯ D E F♯ G A♯ B
• B Melodic minor ascending: B C♯ D E F♯ G♯ A♯ B
• B melodic minor descending: B A G F♯ E D C♯ B

Diatonic scales

• B Ionian: B C♯ D♯ E F♯ G♯A♯ B
• B Dorian: B C♯ D E F♯ G♯ A B
• B Phrygian: B C D E F♯ G A B
• B Lydian: B C♯ D♯ E♯ F♯G♯ A♯ B
• B Mixolydian: B C♯ D♯ E F♯G♯ A B
• B Aeolian: B C♯ D E F♯ G A B
• B Locrian: B C D E F G A 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

Variation of meaning by geographical region

The referent of the musical note B varies by location. See note for a discussion on other differences in letter naming of the notes.

In the United States, Canada, Australia, the United Kingdom, the Republic of Ireland, and the Netherlands, as described above, B usually refers to the note a semitone below C, while B-flatrefers to the note a whole tonebelow C.

However, in Germany, Central and Eastern Europe, and Scandinavia, the label B is used for what, above, is called B-flat, and the note a semitone below C is called H. This makes possible certain spellings which are otherwise impossible, such as the BACH motif.

A b (musical note)

A♭ (musical note)

A♭ (A-flat; also called la bémol) is the ninth semitone of the solfège.