Rodgers Trillium T787, Руководство пользователя

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Pitch Designations
The stops and couplers on your Rodgers T787 each have a pitch designation, listed in “feet”, (8’,
4’, 16’, etc.).
8’ refers to concert pitch ; a note played on an 8’ stop will have an identical pitch
as the same note played on a piano. 16’ represents an octave below concert pitch; a note played
on a 16’ stop will sound an octave below an 8’ stop.
This system of designating pitches represents the approximate length of open organ pipes; the
largest pipe in an 8’ rank is approximately eight feet long; the largest pipe in a 16’ rank is about
sixteen feet long. Other footages and their relationship to concert pitch are listed in the table
below:
Pitch Relationship to concert pitch
32’ two octaves below
16’ one octave below
8’ equal to concert pitch (also known as ‘Unison’)
4’ one octave above
2’ two octaves above
1’ three octaves above
When whole numbers are used (as shown in the table above), it implies that the pitch of the stop
is a certain number of octaves above or below the 8’ pitch.
Mutation stops, on the other hand,
are different in that they have fractions in their pitch designations. This means that their pitch
falls somewhere other than on the octave.
Mutation Common name Relationship to concert pitch
2-2/3’ Nazard one octave and a fifth above
1-3/5’ Tierce two octaves and a third above
1-1/3’ Larigot two octaves and a fifth above
Mutations are most commonly from the flute family and are often used with other flute stops in
solo registrations or ensembles used in early organ music. Because mutations often appear in
divisions with a number of other flute stops, a great diversity of solo color can be achieved by
using various combinations of stops. See the following table for common solo registrations
utilizing mutations.
Registrations Using Mutations With Other Flute Stops
8’ 4’ 2-2/3’ 2’ 1-3/5’ 1-1/3’
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