The young New Hampshire-born, Yale-trained pianist and composer Miles Walter, winner of a handful of auspicious composition prizes, has the floor for the opening movement of his (first?) symphony, a world premiere. From that point on, it’s all-Mendelssohn, which is to say guaranteed bliss. Randall Goosby is the elegant frontman for the Violin Concerto in E minor, op. 64, with its aquiline flights of melody. To close, there are what the program calls “scenes” from A Midsummer Night’s Dream, op. 61. Surely the selections will include the miraculous concert overture, written in the composer’s 17th year, which is no scene but an Olympian overview of the intersecting human and supernatural realms of the play. For the rest, expect excerpts from the incidental music Mendelssohn added (seamlessly) 16 years later, including the fairies’ lullaby for their queen, the willful Titania. Nicholas McGegan, an impish and sprightly conductor, leads the revels. —Matthew Gurewitsch