INSTRUMENTATION, in Music, signifies, in a general sense, the manner in which the different musical instruments in a piece of music are arranged and employed. The different powers and qualities of the instruments, their relative pitch, &c., must all be consulted in producing a good instrumentation, whether in a piece composed for instruments only, or in an instrumental accompaniment to vocal music. A true balance of power must be maintained among the different instruments, otherwise the clearness and brilliancy of the harmony will be destroyed, and the effect confused and unsatisfactory. The best models of judicious instrumentation are the compositions of Haydn, Mozart, Beethoven, Cherubini, Weber, and Mendelssohn. See Music, §§ Accompaniment and Orchestral Music. (G. F. G.)