[4][5] Raised in Port Chester, New York, Gamson studied at the Juilliard School( M.S 1953) and while there founded the American Opera Society (AOS) with Allen Sven Oxenburg in 1950.
The company's first production was Claudio Monteverdi's Il Combattimento di Tancredi e Clorinda for an audience of 50 in the drawing room of a mansion on 5th Avenue in New York City.
These smaller concerts quickly became so popular that the AOS had to move to increasingly larger venues, ultimately using Carnegie Hall as the company's home.
Many of these operas had never been heard in the United States before and featured great vocalists of the period, including Leontyne Price, Jon Vickers and Elisabeth Schwarzkopf and others early in their careers.
[6] While working for the AOS, Gamson appeared as a guest conductor with opera companies and orchestras including the Montreal Philharmonic and Teatro de Bellas Artes in Mexico.
In March 1960 Gamson was an assistant conductor with the New York Philharmonic at Carnegie Hall at the invitation of Leonard Bernstein, leading the orchestra in performances of Henry Brant's Antiphony One.