Having moved through the musical ages with its Lunchtime Classics programs in Duke's Rare Book Room at Perkins Library, members of the resident Ciompi Quartet take on a striking final piece: Belá Bartók's five-movement String Quartet No. 4 in C major challenges traditional tonality, crafting a punctuated progression that captures listeners and sets the piece firmly in any selection of essential chamber music. The free, hour-long program is the last in a four-part series of noon concerts. The series made its Duke Performances debut this season as part of a tiered Ciompi concert experience offering First Course talk-back discussions for $5 in advance of all-out concert hall performances for $20—great strategy for a local institution and new audiences. —Margaret Hair