Complex sentence: On the recommendation of the Choirmaster he traveled to Berlin and studied voice with Ernst Grenzebach who was also the teacher of Lauritz Melchior, Meta Seinemeyer, and Max Lorenz, at the same time he sang second bass in Monti's Operetta Theater.
Split into simpler sentences: On the recommendation of the Choirmaster he traveled to Berlin and studied voice with Ernst Grenzebach who was also a teacher of Lauritz Melchior, Meta Seinemeyer, and Max Lorenz. At the same time he sang second bass in Monti's Operetta Theater.