In an age when jazz is amplified in clubs the size of a breakfast nook, a series called “Jazz Unplugged” promises blessed relief. Dispensing it here are Hamasyan, an Armenian-born pianist who romps blithely from motoric vamps to perfumed modal arabesques, and Akinmusire, whose acrid, utterly original trumpet can evoke, in a single phrase, fragile Milesian lyricism and an antically flatulent balloon. —E.E.