The president of the company Gateway Mastering & DVD, located in Portland, Maine, USA.

Renowned mastering engineer who, as a rule of thumb, is normally credited as 'Bob Ludwig' on pop/rock/mainstream releases and as 'Robert C. Ludwig' or 'Robert Ludwig' on classical recordings. Pre 1972, when mastering generally went uncredited, his initials 'RL' were usually cut into the run-outs in his Sterling Sound (whose wax imprint was 'SS'), and Masterdisk, NY days.

"King" Bob Ludwig, B. Ludwig, Bad Bob Ludwig, BL, Bob, Bob "Bob" Ludwig, Bob "The King" Ludwig, Bob C. Ludwig, Bob Ludvig, Bob Ludwick, Bob Ludwik, Bob Ludwing, Bobby Ludwig, Bub Ludwig, Kevin Gray, Ludwig, Peter Bulckens, R L, R.L., RL, RL., Rob Ludwig, Robert C Ludwig, Robert C. Ludwick, Robert C. Ludwig, Robert C. Ludwiog, Robert C.Ludvig, Robert C.Ludwig, Robert Ludvig, Robert Ludwig, Robet C. Ludwig, The Inimitable Robert C. Ludwig, Боб Людвиг