Listed only by Irwin, who says: A Foundation stop of large scale and loud tone, pitched at 5-1/3' on the manuals, and 10-2/3' on the pedals, forming the third harmonic (the �Twelfth�) of the sub-unison choir of pitches. This stop, which is a Principal or Diapason in most examples, should always be combined with louder ensembles including a 16' manual pitch and a 32' pedal pitch. It speaks at the interval of a fifth above the keys depressed on manuals and pedals, that is at G1 from middle C, and GGG from the pedal's low CCC key. It is similar to the Quint in function. A few stops of this name speak at 10-2/3' on the manuals and 21-1/3' on the pedals, but the names Gross Quint or Grossquintenbass are more appropriate for them. Grand may refer to a large scale, prominent voicing, or to any one of the long series of the sub-unison pitches one octave below the normal meanings in a stop name.