This stop is listed only by Irwin, who says: A stop name that refers to a manual or pedal mixture of unusual completeness in its harmonic pitches. Its open metal (or wood) ranks add a complete chord of harmonics to any combination, solo or ensemble. Its pitches are based on the unison open-pipe partials. The lowest eight are represented. Examples on other pitch series can be formed. . . . Individual ranks in the above mixture are at different degrees of volume, perhaps also different in tone quality, in order to give the sound unity of effect. The octave-sounding ranks are louder than the other ranks, the unison ranks being the loudest. The fifth-sounding ranks are less loud, and perhaps conical in form. The third-sounding ranks are quite soft to keep them from injecting too much sharp quality. The flatted-seventh-sounding ranks are very soft, perhaps Echo Dulcianas, to keep them from being �gritty� in the ear. Audsley mentions it only in passing: �The term grand has been applied to other stops for the purpose of indicating their relative importance; we, accordingly, find such terms as ... Grand Mixture.�
Grand Mixture VII (12-15-17-19-22-26-29); Atlantic City Convention Hall Ballroom, Atlantic City, New Jersey, USA; Kimball 1930.