Short octave
DEFINITION
On an early keyboard instrument, especially an organ, harpsichord, virginal, spinet, or clavichord, a short octave is an arrangement of keys in the lowest octave to enable the performer to play lower notes than the size of the instrument would normally allow. In a short octave, certain tones of the scale that are rarely used are eliminated, and the tones remain are arranged thus:D E B-flatC F G A B Cresult of omitting certain low tones from the ranks of organs resulted in this special arrangement of the lowest keys, which enabled playing big intervals