The Concertino for Horn and Orchestra in E minor, J188 (Op. 45), was composed in 1815 by Carl Maria von Weber. It is an extremely taxing work, whether played on the natural horn for which it was written, or on the modern valve horn. The soloist is accompanied by a small orchestra. It requires, among other feats, that the player produce what is in effect a four-note chord using the interplay between humming and the sound from the instrument, a technique known as multiphonics.