Musical note standardised at 440 Hz, lying in the octave containing notes from C (middle C) to B. The lowest note on most pianos is A, the highest C. The MIDI system for electronic musical instruments and computers uses a straight count starting with note 0 for C at 8.1758 Hz up to note 127 for G at 12,544 Hz. A written note can also have a note value, a code that determines the note's relative duration. In order of halving duration, they are: double note (breve); whole note (semibreve); half note (minim); quarter note (crotchet); eighth note (quaver); sixteenth note (semiquaver).;
How Sacred Harp music is sung is a note whose duration is increased by half the duration of the base note. It is so called because musical notation uses a dot to express this durational ratio. Traditional Sacred Harp singers often "add dots" to their music, in the sense that they will make the notes falling on the strong musical beat about one and a half times as long as written, with the following note shortened to half of its written duration in compensation. The great majority of the cases seem to involve substitution of the sequence "dotted eighth + sixteenth" for what is written as