Under his leadership, Mercury began releasing its notable "Living Presence" series of classical recordings. Hall worked closely with sound engineering pioneer, C. Robert Fine (né Clarence Robert Fine; 1922–1982). Fine's mobile sound studio toured the midwest, recording performances by the Detroit, Louisville, and Minneapolis symphonies and musical groups at the Eastman School at the University of Rochester. A 1955 recording of the Minneapolis Symphony performing Tchaikovsky's 1812 Overture under the baton of Antal Doráti became the best selling classical record of the decade. In 1956, Hall was awarded a Fulbright Teaching Fellowship, which enabled him to spend a year at the University of Copenhagen (Denmark) teaching advanced recording techniques to Danish engineers and musicians. Hall had long been interested in Scandinavian music, having directed the music center at The American-Scandinavian Foundation in New York from 1950 to 1957. Upon returning to the United States in the fall of 1957, Hall became music editor of Hi-Fi/Stereo Review (later Stereo Review). Hall contributed reviews of classic music and articles to the magazine until it folded in 1998. In his writings, Hall championed contemporary music. His 1964 article on Charles Ives included the first full discography of Ives's recordings. In 1963, Hall became president of Composers' Recordings, Inc., a nonprofit record label devoted to recording and distributing the work of contemporary composers. Among the notable recordings produced under his leadership were a series of performances by avant-garde composer Harry Partch. In 1967, Hall was the founding curator of the Rodgers and Hammerstein Archives of Recorded Sound, one of the units of the New York Public Library for the Performing Arts at Lincoln Center. There he pioneered new techniques of cataloging recorded material as one of the initiatives of the Research Libraries Group, a consortium of the nation's leading research libraries. Hall and his associates also released an important collection of historic sound recordings, The Mapleson Cylinders, which captured the singing of Metropolitan Opera stars of the early twentieth century. This recording won a Grammy Award for Best Historical Album in 1986. During this period, Hall helped to found the Association for Recorded Sound Collections (ARSC) in 1966. He served as the group's president from 1980 through 1982. In 2002, he received the ARSC Award for Distinguished Service to Historical Recordings. In 1986, Hall retired to the seaside village of Castine, Maine, where he continued to write record reviews and consult on recording projects.