Described only by Irwin, who says: �A manual or pedal mixture composed of Foundation ranks of open metal construction, designed to amplify the sub-unison series of pitches.� Hopkins & Rimbault give the composition below, but do not define the name.

Quint Mixture II (12,15), Great; The Grove Organ, Tewkesbury Abbey, Gloucestershire, England; Michell & Thynne 1885.

Quint Mixture IV (15,19,22,26), Swell; Bath Abbey, Bath, England; Hill 1868.

Quint Mixture V, Swell; Woolsey Hall, Yale University, New Haven, Connecticut, USA.