C or Do is the first note of the C major scale, the third note of the A minor scale (the relative minor of C major), and the fourth note (G, A, B, C) of the Guidonian hand, commonly pitched around 261.63 Hz. The actual frequency has depended on historical pitch standards, and for transposing instruments a distinction is made between written and sounding or concert pitch. In English the term Do is used interchangeably with C only by adherents of fixed-Do solfège; in the movable Do system Do refers to the tonic of the prevailing key. Frequency Historically, concert pitch has varied. For an instrument in equal temperament tuned to the A440 pitch standard widely adopted in 1939, middle C has a frequency around 261.63 Hz (for other notes see piano key frequencies). Scientific pitch was originally proposed in 1713 by French physicist Joseph Sauveur and based on the numerically convenient frequency of 256 Hz for middle C, all C's being powers of
C o Do es la primera nota de la escala mayor C, la tercera nota de la escala menor A (la menor relativa de C mayor), y la cuarta nota (G, A, B, C) de la mano guidoniana, comúnmente punzado alrededor de 261.63 Hz. La frecuencia real ha dependido de los estándares de pitch históricos, y para la transposición de instrumentos se hace una distinción entre escrito y sonido o pitch concerto. En inglés el término Do se utiliza intercambiablemente con C sólo por los adherentes de solfège fijo-Do; en el sistema movible Do Do se refiere al tónico de la clave predominante. Frecuencia Históricamente, el pitch de concerto ha variado. Para un instrumento en igual temperamento ajustado al estándar de pitch A440 ampliamente adoptado en 1939, el medio C tiene una frecuencia alrededor de 261.63 Hz (para otras notas de piano ver frecuencias clave).