In 1924, a 15-year-old Carter was in the audience when Pierre Monteux conducted the Boston Symphony Orchestra (BSO) in the New York première of "The Rite of Spring". Carter later came to appreciate the American ‘ultra-modernists – namely Henry Cowell, Edgard Varèse, Ruth Crawford and, later, Conlon Nancarrow. Ives often accompanied Carter to BSO concerts conducted by Serge Koussevitzky, who programmed contemporary works frequently, and then returned to Ives' home to critique and parody the so-called ‘tricks’ of Debussy, Stravinsky or Prokofiev – who were composing European 'new music' Ives considered only 'superficially modern'.