This season the Discovery Ensemble, led by the dynamic young conductor Courtney Lewis, seems determined to build on the momentum generated by the artistry it has placed on view since its founding in 2008. To that end, it has moved all its concerts from Sanders Theatre to the more symbolically central Jordan Hall, it has announced plans for a new Chamber Players series, and it has taken aim at both larger-scale repertory and a handful of seldom heard works.
Discovery’s season-opener on Sunday afternoon charted a refreshingly uncommon flight path. Instead of the typical overture-concerto-symphony format, this performance began with Mozart’s Piano Concerto No. 20 and from that miracle of early classical invention and ratiocination, plunged the listener into the ghostly, disorienting landscapes of Ligeti’s “Melodien.” After intermission, where a hefty Romantic symphony might have offered the ears more conventional reassurance, Lewis and company instead concluded with the majestic strangeness of Sibelius’s Symphony No. 6, a work whose grasp of melody seems at times no less elusive than the avant-garde tone poem that here preceded it.