B (musical note)
B, also known as Si, Ti, or, in some European countries, H, is the seventh note of the fixed-Do solfège. It has an enharmonic equivalent of C♭, which is by definition a diatonic semitone above B♭. B is also enharmonic with A
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When calculated in equal temperament with a reference of A above 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.
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-flat refers to the note a whole tone below 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.
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