The Lettermen The Lettermen is a musician known for their adult standards, bubblegum pop, easy listening, lounge and vocal harmony group music. Top tracks by The Lettermen Related artists Harpers Bizarre Bobby Sherman The Four Aces Rita Coolidge Lou Christie Marco Sison Lenny Welch Nat King Cole Johnnie Ray Pat Boone Bobby Goldsboro Bobby Vinton The Spiral Starecase The Cascades Ray Peterson Mel Carter Wishful Thinking