You’d be forgiven for thinking that Mozart’s Clarinet Concerto was composed for the clarinet we all know—the sleek liquorice black instrument beloved of classical, jazz and marching band musicians. But, in a bit of a twist, it turns out that it was originally written for the basset clarinet, a forerunner of the modern instrument that Mozart’s friend Anton Stadler had a hand in developing. Now, the OAE’s principal clarinettist, Katherine Spencer, has had one made just to play Mozart’s last piece—and you can hear it in action at this community open rehearsal.