FACH

This article is about music. For the Fuerza Aerea de Chile, see Chilean Air Force.The German Fach (pl. Fächer, literally "compartment") (IPA pronunciations: , ) system is a method of classifying singers, primarily opera singers, by the range, weight, and color of their voices. It is primarily used in Europe, especially in German-speaking countries and in repertory opera houses.The Fach system is a convenience for singers and opera houses. A singer who is identified as being of a certain Fach will usually be asked to sing only roles that belong to that Fach. This prevents a singer from being asked to sing roles which he or she is incapable of performing. Opera houses keep lists of available singers by Fach so that when they are casting roles for an upcoming production, they do not inadvertently contact performers who would be inappropriate for the part.
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n. knowhow, proficiency or skill at a particular thing, expertise; area, subject, topic, branch