Building for Clarity
So far, this lesson has included only unison- or octave-sounding stops and chorus mixtures. These are the main building blocks in chorus registration. However, some mutations can be added to chorus registrations for color.
A 2 2/3' stop (Nazard, Nasat, Quinte, etc.) adds a relatively low fifth-sounding pitch. It adds a certain gravity and thickness to the ensemble, thereby reducing clarity. The degree of its effect will depend on the relative strength of the stop. Mutations on the Great are nearly always stronger than those on other manual divisions, since they are usually voiced as principals. Those on the Swell and Choir are usually voiced as flutes.
It is generally best to avoid using the 2 2/3' stop as the highest pitch in a chorus registration.
