The B footjoint is longer and allows the flutist to be able to play the note "B" at the lowest edge of the flute's range (the lowest note of a C footjoint is "C"). While a flute with a C footjoint has a bright and resonant sound, a flute with a B footjoint has a more dark and glossy sound. Because of this, flutes with a B footjoint are sometimes selected for their tonal characteristics rather than a technical reason.
Yamaha flute models with a B footjoint can be identified by the letter "H" in the model number (ex. YFL-361H, YFL-674HCT). The note B natural was identified by the letter "H" in some traditional European styles of musical notation, thus the use by Yamaha of the letter "H" to indicate a flute has a B footjoint.
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