For most of his career trumpeter Dave Douglas has started new bands fairly regularly. That can probably be partly explained by the current economy of jazz, which makes it hard for any single group to get enough work to sustain itself—even bandleaders need multiple projects. But just as important is Douglas’s musical curiosity. He’s always been eager to use specific groups to explore specific ideas—scoring silent films, working with electronics, creating string-driven modern chamber jazz. In recent years, however, he’s slowed down, sticking with a smaller number of ensembles, which makes the appearance of a new one particularly newsworthy. On September 25 he’s releasing an album called Be Still (on his own Greenleaf imprint) with a great new quintet featuring saxophonist Jon Irabagon, pianist Matt Mitchell, bassist Linda Oh, and drummer Rudy Royston.