A demo of St. Anne's (North Church):
First 25 seconds "Swell Unison Off" = ON
then turned OFF to bring in the lower sound.
----Swell Unison Off ---
Swell Octave - on
Lieblich Bourdon 16'
Geigen Principal 8'
Contra Fagotto 16'
Just to compare. Also demonstrates St. Anne's "Unison Off" does allow the couplers for Swell Octave to produce sound alone.
Works with Suboctave and Swell-to-Pedal too.