Rodgers Trilogy - Organ Features: Couplers, Percussions, and Tremulants

8
COUPLERS, PERCUSSIONS, TREMULANTS, AND NON-SPEAKING STOPS
COUPLERS
There are three couplers on the 32-B and the Trilogy, Swell to Great, Swell
to Pedal, and Great to Pedal. The Swell to Great coupler is used principally
for combining the romantic voices (principally the Chorus Reeds) with the
Great Organ for greater brilliance and body in full organ effects. The Pedal
couplers furnish the necessary upper pitches to the Pedal, and give it greater
definition.
- PERCUSSIONS
The
Carillon is derived from a cluster of sustained Flute part:ials, assembled
about a given pitch so as to duplicate the harmonic structure of tuned bells.
The Harp is another sustained voice, suggestive of steel bars being struck by
small felt hammers. When used in arpeggios, it is most useful.
CHIFF
The 8' Quintade (Chiff tab on earlier models) on the Choir is used when the
Baroque accent is desired on the Choir Flutes. When depressed, it adds the
12th momentarily to each note as it is keyed. This effect is simultaneously
added to all Choir Flutes and mutations.
TREMULANTS
There are three tremulants on the Trilogy; two on the 32-B. The one con-
trolled by the tab on the Swell places a tremolo on all of the Diapason, Reed,
and String voices, as well as the Swell Flutes. The Great and Choir Flute
Tremulant is controlled by the Tremulant stop key on the Choir. The Trilogy
has two tremulants for these Flutes, Light and Full. In addition, the Echo
controls on the Trilogy provide for the addition of a Leslie vibrato effect on
the Great and Choir Flutes.
FULL CHORUS CONTROL
This
tab, when depressed, slightly detunes the Flute generator set and the
Main generator set. This imparts a "sound in motion" effect to any music
played when the Flutes are used in combination with the Diapason or Strings.
The resulting effect is slower than a celeste, but has much of the same warmth
of tone as a celeste.