A Dictionary of Music and Musicians/Acuteness

ACUTENESS. A musical sound is said to be more acute as the vibrations which produce it are more rapid. It is said to be more grave as the vibrations are slower. Thus of the two notes
{ \override Score.TimeSignature #'stencil = ##f \time 2/4 { c''2 \bar "||" } }
{ \override Score.TimeSignature #'stencil = ##f \time 2/4 { c'2 \bar "||" } }
the former of which is produced by 512 vibrations per second, and the latter by 256, the former is called the more acute, the latter the more grave. The application of these terms is not easy to account for. 'Acute' means sharp in the sense of a pointed or cutting instrument, and 'grave' means heavy; but there is no direct connection between the impression produced by rapid vibrations on the ear and a sharp edge, nor between the effect of slow vibrations and the force of gravitation; neither are these terms consistent, for one is not the antithesis to the other. To be correct, either the slow vibration-sound should be called 'blunt,' or the quick one 'light.' The terms however are as old as the Greeks, for we find them applied in the same way by Aristides Quintilianus, who uses ὀξύς to denote the quick vibrating sounds, and βαρύς to denote the slow ones, and they have been transmitted through the Latin acer and gravis down to our day. Other figurative terms are similarly applied. 'Sharp,' for example, is clearly synonymous with 'acute,' both in derivation and application; but 'flat' has no analogy with grave or heavy. It is a more correct antithesis to acute or sharp, for one can fancy a blunt edge to be in some degree flattened, and a blunt needle would, under the microscope, undoubtedly show a flat surface at its end.

There are however two other words still more generally used. These are 'high' and 'low'; the former denoting greater, the latter less, rapidity of vibration. The application of these is the most puzzling of all, as there is no imaginable connection between any number of vibrations per second, and any degree of elevation above the earth's surface. It is very customary to use the figure of elevation to express an idea of magnitude or superiority, as high prices, high pressure, elevation of character, and so on; and if the vibration-numbers corresponding to any note had been a matter of general knowledge in early ages, we might have assumed that the terms had been chosen on this principle. But the vibration-numbers are quite a modern discovery, not even yet generally believed in by practical men: and unfortunately such relations of sound as do address themselves to the eye point entirely the other way; for, as already stated, the grave sounds convey most strongly the idea of magnitude, and therefore by analogy these ought to have been called high rather than low.

The ancients appear to have imagined that the acute sounds of the voice were produced from the higher parts of the throat, and the grave ones from lower parts.[1] And this has been supposed by some writers to have been the origin of the terms; but the idea is incorrect and far-fetched, and can hardly be considered a justification.

As soon as anything approaching the form of musical notation by the position of marks or points came into use, the terms high and low were naturally seized upon to guide such positions. Thus our musical notation has come into being, and thus the connection between high notes and quick vibrations has become so firmly implanted in our minds, that it is exceedingly difficult to bring ourselves to the appreciation of the truth that the connexion is only imaginary, and has no foundation in the natural fitness of things.

[ W. P. ]

  1. See passage from Aristides Quintillanus, quoted in Smith's Harmonics, p.2.