These arrangements have been available for many years from Corniworld, an excellent boutique publisher of music for horns. Check them out and consider buying other titles from their catalogue as well.
4 horns
Johann Sebastian Bach – Air from Suite no.3 in D BWV1068 (buy)
Ludwig van Beethoven – Coriolan overture (buy)
Anton Bruckner – Fuge in d minor (buy)
Claude Debussy – Le petit negre (original in C, arranged in F) (buy)
5 horns
Ludwig van Beethoven – Quintet op.4 (buy)
Georges Bizet – Carmen fantasy (buy)
Claude Debussy – Children’s corner no.2 “Jimbo’s lullaby” (buy)
Claude Debussy – Children’s corner no.6 “Golliwogg’s cake walk” (buy)
Claude Debussy – Elegie (buy)
Claude Debussy – Le petit negre (original in C, arranged in F) (buy)
Claude Debussy – Preludes book 1 no.6 “Footprints in the snow” (buy)
Claude Debussy – Preludes book 1 no.8 “The girl with the flaxen hair” (buy)
Claude Debussy – Preludes book 2 no.6 “General Lavine” (buy)
Claude Debussy – Reverie (buy)
Claude Debussy – Suite Bergamasque no.3 “Clair de lune” (buy)
Claude Debussy – Suite Bergamasque no.4 “Passepied” (buy)
Edvard Grieg – Peer Gynt suite (buy)
Claudio Monteverdi – L’incoronazione di Poppea (buy)
Claudio Monteverdi – Si ch’io vorrei morire (buy)
Claudio Monteverdi – Toccata from Orfeo (buy)
Wolfgang Amadeus Mozart – Magic flute selections (buy)
Wolfgang Amadeus Mozart – Symphony no.40 mvt.1 (buy)
Camille Saint-Seans – Morceau de concert (solo, 4 accompaniment) (buy)
Carl Maria von Weber – Concertino (solo, 4 accompaniment) (buy)
6 horns
Ludwig van Beethoven – Sextet op.81b (2 solo, 4 accompaniment) (buy)
8 horns
Ludwig van Beethoven – Fidelio overture (original in E, arranged in E flat) (buy)
Ludwig van Beethoven – Rondino (buy)
Hector Berlioz – La fuite en Egypte (original in f#, arranged in f) (buy)
Georges Bizet – L’Arlesienne suite (Prelude, Intermezzo, Adagietto, Farandole) (buy)
Johannes Brahms – Academic festival overture (buy)
Anton Bruckner – Ave Maria gratia plena (buy)
Felix Mendelssohn-Bartholdy – Paulus overture (buy)
Maurice Ravel – Menuet antique (buy)
Giacchino Rossini – Tancredi sinfonia (original in D, arranged in C) (buy)
Giacchino Rossini – William Tell overture (original in e, arranged in c) (buy)
Carl Maria von Weber – Der Freischutz overture (buy)
Carl Maria von Weber – Der Freischutz incidental music (Bauern-Marsch, Waltzer, Jagerchor) (buy)
12 horns
Gaetano Donizetti – Daugher of the regiment fantasy (buy)
Gaetano Donizetti – Lucia di Lammermoor fantasy (buy)
Harry Gregson-Williams / John Powell – Chicken Run Main Titles (with 3 percussion & timpani) (buy)
Giacomo Puccini – La rondine fantasy (buy)
Robert Schumann – Symphony no.3 mvt.4 (with timpani) (buy)
Richard Strauss – Alpine Symphony (abridged) (8 horns and 4 Wagner tubas)
Richard Strauss – Ein Heldenleben (abridged) (buy) (watch)
Richard Strauss – Till Eulenspiegel
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