In music, instrumentation is the particular combination of musical instruments employed in a composition, and the properties of those instruments individually. Instrumentation is sometimes used as a synonym for orchestration. This juxtaposition of the two terms was first made in 1843 by Hector Berlioz in his Grand traité d’instrumentation et d’orchestration modernes, and various attempts have since been made to differentiate them. Instrumentation is a more general term referring to an orchestrator's, composer's or arranger's selection of instruments in varying combinations, or even a choice made by the performers for a particular performance, as opposed to the narrower sense of orchestration, which is the act of scoring for orchestra a work originally written for a solo instrument or smaller group of instruments .