In 1962 Young wrote "The Second Dream of the High-Tension Line Stepdown Transformer". One of "The Four Dreams of China", the piece is based on four pitches, which he later gave as the frequency ratios: 36-35-32-24 (G, C, +C#, D), and limits as to which may be combined with any other. Most of his pieces after this point are based on select pitches, played continuously, and a group of long held pitches to be improvised upon. For "The Four Dreams of China" Young began to plan "Dream House", a light and sound installation conceived as a "work that would be played continuously and ultimately exist as a 'living organism with a life and tradition of its own,'" where musicians would live and create music twenty-four hours a day. He formed the music collective Theatre of Eternal Music to realize "Dream House" and other pieces. The group initially included calligrapher and light artist Marian Zazeela (who married Young in 1963), Angus MacLise, and Billy Name. In 1964 the ensemble comprised Young and Zazeela, John Cale and Tony Conrad (a former Harvard mathematics major), and sometimes Terry Riley (voices). Since 1966 the group has seen many permutations and has included Garrett List, Jon Hassell, Alex Dea, and many others, including members of the 60s groups.