Able to swing instantly and effortlessly between seductive and triumphant, the French horn is one of the orchestra’s most versatile and expressive instruments. And with its glistening, twisting coils of brass tubing, it’s one of the most visually impressive, too. But when composers really want the French horn to play a starring part, they ask players to put their “bells up”—the French horn equivalent of turning the volume up to 11. The player inverts the horn so that its flared end, or bell, is directed up and out towards the audience. “It’s always a beautiful sight,” Sarah Willis tells Apple Music Classical, “a whole section of glittering French horns with their bells up, playing their hearts out and their sound soaring over the orchestra.” After the rousing call of the hunting horn in Bach’s Brandenburg Concerto No. 1, Willis showcases Mozart’s sophisticated music for the instrument. “We horn players are so lucky that Mozart wrote us four concertos,” says Willis. “I grew up listening to the Dennis Brain and Günter Högner recordings and, decades later, took the plunge to record them myself with the Havana Lyceum Orchestra in Cuba.” For a real taste of “bells up”, the fourth movement of Mahler’s Symphony No. 1 takes some beating. On the score’s final page, Mahler instructs the whole horn section to stand and play right until the end of the piece which, says Willis “has a fantastic effect on the audience”. Her playlist also includes Richard Strauss’ Till Eulenspiegel’s Merry Pranks, with its virtuosic horn introduction, and the finale of Stravinsky’s Firebird that shows off the the instrument’s uncanny ability to sound as if calling from a distance. And which French horn playlist would be complete without John Williams? “Williams writes so perfectly for the French horn,” says Willis, “and has used the instrument to depict everything from the hero to the romantic interest, the enemy to the intergalactic adventurer and battle scenes in between. His music is unimaginable without our beloved instrument.” Each track on this playlist makes Willis proud to be a horn player. “I would put my bell up for every one of them!” she adds.