APPENDIX II

DEFINITIONS

amplifier.
A device to magnify electrical impulses, usually including one or more electron tubes.
clavier.
A series of keys by which a musical instrument is played. It applies to the manual keyboards as well as the pedal keyboard console. The case containing the playing and tone control mechanism of an organ.
diatonic.
Pertaining to or designating a standard major or minor scale of eight tones to the octave.
f, forte.
Loud, powerful; a direction, opposed to piano.
ff, fortissimo.
Very loud.
fff, fortississimo.
Louder than ff.
fifth.
A musical interval embracing five diatonic degrees or steps of a musical scale.
fundamental.
The sound, without harmonics, having the number of vibrations characteristic of the pitch produced.
harmonics.
Tones of various pitches sounding simultaneously.
intensity.
Magnitude or amplitude of sound.
m, mezzo.
Mean, not extreme.
mf, mezzo forte.
Medium loud.
mp, mezzo piano.
Medium soft.
octave.
An interval embracing eight diatonic degrees or steps of a musical scale; a tone or note at this interval.
p, piano.
Soft.
pedal.
A lever operated by the foot.
pedal clavier.
Organ keyboard operated by the feet.
percussive.
Initial sharp attack as compared with gradual attack.
pitch.
That property of a musical tone which is determined by the number of sound wave vibrations which strike the ear per second; the greater the number of vibrations per second the higher the pitch.
quality.
That property or color of a tone which may distinguish it from another tone having the same pitch and loudness.
shaded pole motor.
A motor, the speed of which varies with fluctuations of power supply.
sound.
The sensation of hearing; that which is heard; the vibrational energy which occasions such a sensation.
swell pedal.
A pedal operated by the foot to control the volume of tone produced by the manuals and pedal clavier of the organ.
synchronous motor.
A motor, the normal operating speed of which is constant and exactly proportional to the frequency of the current by which it is driven.
third.
An interval of three diatonic degrees or steps of a musical scale.
tone.
A sound having such regularity of vibration as to impress the ear with its individual character, especially as regards pitch. Tone is often used to describe the qualities of combined notes consisting of a fundamental and associated harmonics. (See app. III for descriptions of tone qualities associated with the electronic organ tone selection keys.)
tremolo.
A steady or constant undulation of tone, producing a pleasing rhythmic effect on the ear.
twelfth.
An interval of 12 diatonic degrees, or of an octave and a fifth, of a musical scale. .
vibration.
A periodic motion of the particles of an elastic medium, such as air, in alternately opposite directions from a position of equilibrium, as when a stretched cord produces musical tones or particles of air transmit sounds to the ear.