Offstage brass and percussion

An offstage brass and percussion part is a sound effect used in classical music, which is created by having one or more trumpet players (also called an offstage trumpet call), horn players, or percussionists from a symphony orchestra or opera orchestra play a note, melody, or rhythm from behind the stage. This creates a distant, muted effect which composers use to suggest "celestial voices", melancholy, or nostalgia, or to create a haunting effect. An offstage part may be requested by the use of the German instruction "auf dem Theater".

In Act III of Berlioz's opera Les Troyens, a group of offstage trumpets plays a distorted-sounding fanfare along with cornets to create an unusual dramatic effect. In Beethoven's overture for Leonore Overture and in Fidelio he used an offstage trumpet call. In Respighi's The Pines of Rome, he uses an offstage trumpet for "Pines Near a Catacomb"; after the low strings play solemn chords, and the trombones play a simple, ancient-sounding Gregorian chant-style melody, an offstage trumpet introduces the piece's second theme. Richard Strauss used offstage trumpets during a battle scene in Ein Heldenleben ("A Hero's Life"). Aaron Copland's Quiet City used an offstage trumpet. Gustav Mahler's Symphony No. 2 uses an offstage brass ensemble of trumpets, French horns, and percussion. While the offstage trumpet's distant sound can create an emotional effect, critic Maurice Brown warned in 1971 that it can become an overused cliché.

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