Pacifica’s final concert celebrates the life of the American composer Ben Johnston with his one-movement quartet based on the famous hymn Amazing Grace alongside Dvořák’s folk-inspired melodies. Ben Johnston was famous for his obsession with just intonation. In this quartet he excitingly gives the famous hymn the microtonal treatment. Dvořák’s final quartet was begun in New York and completed in Prague, warm, generous, joyful music in the composer’s late manner. Shostakovich’s towering Piano Quintet opens with a Prelude and Fugue and a piano solo that clearly reflect the presence of Bach in a work that combines perfection of form with episodes of deepest pain, brilliant wit, uncouth barbarities and popular tunes.