The music of 20th-century German composer Paul Hindemith has a reputation for being stodgy and academic. It's an unfair characterization; Hindemith was one of those composers caught in a stylistic purgatory (the last century was littered with fellow travelers). His work was considered too modern and decadent by the Nazis, but after the war, the reigning avant-garde found his music to be old-school. It didn't stop him from writing reams of stuff, and he was not without his champions, notably Eugene Ormandy and the Philadelphia Orchestra. At his best, Hindemith produced music of sinew, impeccable logic and a craggy sort of beauty. The Philadelphia Chamber Music Society thinks enough of the man and his music that they will close their season with an all-Hindemith concert, as played by a wonderful ensemble of veteran chamber players. The program also highlights Hindemith's interest in offbeat instruments, with the inclusion of the Trio for Heckelphone, Viola and Piano. A string quartet and a string trio are also on tap.