Known for his strong and beautiful sound, Mergen is currently a member of the trumpet/cornet section of “The President’s Own” United States Marine Band. He also performs with the Blossom Festival Band in Ohio and is a founding member of Valor Brass. In addition, Mergen has performed with the National Symphony Orchestra in Washington, D.C., the Washington Symphonic Brass, the Singapore Symphony in the Republic of Singapore, the Harrisburg Symphony in Pennsylvania and the Choral Arts Society of Washington. He was a Fellow at the Tanglewood Music Center in Lenox, Massachusetts, and attended the Aspen Music Festival. He has worked with conductors Seiji Ozawa, Leonard Slatkin, Osmo Vanska, John Williams and Bramwell Tovey.