Thomas Hampson's early biography sounds like that of the all-American boy. He played basketball, baseball, golf and tennis, and was a student leader in high school. It was a Catholic nun, Sister Marietta Coyle (herself a pupil of the great Lotte Lehmann) who turned the Seventh Day Adventist youth towards a singing career, and, as they say, he's never looked back. Unlike many a famous singer, he tailors his operatic life to fit in with his concert activities. And his performing ideal is not the common one of projection, but rather of drawing his listeners in. His voice is of a beauty to facilitate his philosophy of performance, and his musical intelligence enables him to espouse the paradox of Gerard Souzay's remark that "Interpretation is for people who don't get it in the first place!" Sample Hampson's directly appealing art at the National Concert Hall (01-4751572) on Tuesday in a programme that includes Schubert, Mahler, Ned Rorem, Hindemith and Bernstein.