Acoustics

ACOUSTICS. - As a science, it deals with all the qualities of sound in itself or in relation to certain places where sounds are heard. With regard to the liturgical use of acoustics, a distinction must be made between the study of sound as a constituent element of chant and the sound of instruments, such as the organ and bells. Prior to Gregorian chant, the Hellenes and the Greco-Romans regarded the study of sound as part of harmonics, that is, of the proper arrangement of small or large intervals, diatonic or chromatic, symphonic or diaphonic, successive or simultaneous. In liturgical use, instruments were excluded both for reasons of acoustics and because of the secular use to which they were devoted. This exclusion does not, however, apply to all instruments, since some are used to give the pitch or to prelude the chant to be performed.