TONE

, or Tune, in Music, a property of sound, by which it comes under the relation of grave and acute; or the degree of elevation any sound has, from the degree of swiftness of the vibrations of the parts of the sonorous body. |

For the cause, measure, degree, difference, &c, of Tones, see Tune.

The word Tone is taken in four different senses among the ancients. 1, For any sound, 2, For a certain interval; as when it is said the difference between the diapente and diatessaron is a Tone. 3, For a certain locus or compass of the voice; in which sense they used the Dorian, Phrygian, Lydian Tones. 4. For tension; as when they speak of an acute, a grave, or a middle Tone. Wallis's Append. Ptolom. Harm. p. 172.

Tone is more particularly used, in music, for a certain degree or interval of tune, by which a sound may be either raised or lowered from one extreme of a concord to the other, so as still to produce true melody.

In tempered scales of music, the Tones are made equal, but in a true and accurate practice of singing they are not so. Pepusch, in Philos. Trans. No. 481, p. 274.

Beside the concords, or harmonical intervals, musicians admit three less kinds of intervals, which are the measures and component parts of the greater, and are called degrees.

Of these degrees, two are called Tones, and the third a semitone. Their ratios in numbers are 8 to 9, called a greater Tone; 9 to 10, called a lesser Tone; and 15 to 16, a semitone.

The Tones arise out of the simple concords, and are equal to their differences. Thus the greater Tone, 8 : 9, is the difference of a 5th and a 4th; the less Tone 9 : 10, the difference of a less 3d and a 4th, or of a 5th and a greater 6th; and the semitone 15 : 16, the difference of a greater 3d and a 4th.

Of these Tones and semitones every concord is compounded, and consequently every one is resolvable into a certain number of them. Thus the less 3d consists of one greater Tone and one semitone: the greater 3d, of one greater Tone and one less Tone: the 4th, of one greater Tone, one less Tone, and one semitone: and the 5th, of two greater Tones, one less Tone, and one semitone.