Juventas New Music Ensemble, led by Medford composer and conductor Oliver Caplan, continues its 2020-21 virtual concert season with "The Voice of the Rain," featuring music inspired by autumn and nature. "Watershed," a piece Caplan composed and scored for flute, clarinet, horn, cello and piano, was inspired by the Mystic River corridor in Medford. "Walks along the river have helped me get through this past year," Caplan says. "Even on the most difficult days, the beauty of nature calms my…