CONCORDS, in Music, or Consonant Intervals, arc such as have a pleasing effect on the ear, whether their limiting notes are heard in succession or melody, or arc sounded together in consonance or harmony. A knowledge of the true principles, on which this peculiar property, of certain consonances or intervals, called concords, depend, by which they affect the ears of all persons (though in different degrees,) with delight and pleasure, while the greater part of the other musical in tervals have a contrary effect, or excite a grating and rather disagreeable sensation on the ear, and arc called discords, remains yet among the desiderata in this sci ence ; we have said the greater part of the other musi cal intervals rank as discords, because, for reasons that seem still more difficult to discover, all the concords ad mit of a slight deviation, either as to excess or defect, without becoming actually disagreeable, nor indeed do their peculiar characters seem to be much altered, ex cept by the obtrusion of a periodical noise, or audible phenomena, called a beat, or beatings, very different from a musical sound, that accompanies the hearing of all such imperfect or tenOcred concords ; and such beats vary in their frequency of occurrence, and disagreeable effect, with (though not proportionate to) the degree of imperfection in such imperfect concords. See our arti
cle BEATS.
This phenomenon, of slow and audible beats, which accompanies the concords, when slightly altered from their true ratios or perfection, has been proposed by some, as a character of concord ; but as this requires the same test, viz. an appeal to the sense of hearing or the judgment of the ear, to discover its existence, as it does to discover their pleasing effect, it fails of that general characteristic, or inherent property, which ought to dis cover itself in the ratios or other methods of expressing musical intervals, that have not actually been heard, and discover beforehand whether they would prove con cords or discords.
The concurrent experience of all musicians, and of others who have experimented on musical sounds and consonances, is, that the following intervals are concords, viz.
C I 5rd 111, 4th , S 6' , vt ,-. S d , s Li 4 3 " 5' 4 3 yin Mal X 1 1 (II XII 15th XIII XV 17th xv1118th I 5 2 3 4 1 1" II 1 V 1 xix 20th xx XXII 24th XXIV 25th xxvi 27th xxvit 1 a i IV A XXIX 31st xxxi 32d xxxiii 34th xxxiv XXXVI I 5 I a 1 5 3 A