User Guide

356 Chapter 22 EVB3
Note: 2 2/3' is the fifth over 4'. 1 3/5', is the major third over 2'. 1 1/3' is the fifth over 2'.
In the bass range, this can lead to inharmonic tones, especially when playing bass lines
in a minor key. This is because mixing 2', 1 3/5' and 1 1/3' results in a major chord.
Residual Effect
The residual effect is a psychoacoustic phenomenon. Human beings can perceive the
pitch of a note, even when the fundamental is completely missing. If human beings
didn’t hear this way, it would make listening to music with a kitchen radio impossible.
Its speaker will never play back the fundamental of the bass line, as this frequency is far
below the range that the speaker can transmit. If you pull out all registers of the
drawbar organ, except for the fundamental—16', you’ll still perceive the same pitch.
The sound becomes thinner, with less bass and less warmth, but the pitch remains the
same.
Setting drawbar registrations often involves this psychoacoustic phenomenon. In the
lower octaves, mixing the 8' and 5 1/3' sine drawbars creates the illusion of a 16' sound,
although the frequency is missing. Old pipe organs also make use of the residual effect,
by combining two smaller pipes, eliminating the need for long, heavy, air-hungry, and
expensive giant pipes. This tradition is continued in modern organs, and is the reason
for arranging the 5 1/3' under 8: The 5 1/3' tends to create the illusion of a pitch that is
one octave lower than 8'.