SWAMPSCOTT – Swampscott, Salem and Marblehead high school choruses are reuniting for the seventh annual “Together In Concert” this Sunday.Each choral group will present an individual program then all three choruses will perform as a group. The combined chorus will perform “Impossible Dream” from the Broadway show “Man of La Mancha” under the direction of Swampscott High School’s James Pearse.”We are looking forward to having the Marblehead and Salem choruses perform with us in our new facility,” he said. “It’s a perfect venue for this event.””Together In Harmony” is directed by Pearse, Amanda Roeder of Marblehead and Steve Black of Salem. Swampscott resident Alan Samiljan, who came up with the idea for the first “Together In Harmony” concert is acting as the host and proceeds from the event will go to the choral programs at all three high schools.The concert will be held at 2 p.m. in the auditorium at Swampscott High School, 200 Essex St. Tickets will be available at the door and are $10 for adults and $5 for senior citizens and students.