Oliver Daniel (1911–90) was an arts administrator, pianist, radio producer, and author. He joined CBS in 1942 and produced and directed a number of music programs for the company, including 20th-Century Concert Hall and Invitation to Music. From 1954 to 1977 he was director of the concert music division of BMI. In 1954 he cofounded Composers Recordings, Inc. (CRI) with the composers Otto Luening and Douglas Moore. For many years he promoted the works of contemporary composers, including Charles Ives and Henry Cowell. In this letter, RK reminds Daniel that he was responsible for Henry Cowell writing Set of Four for RK in 1960.

May 19, 1975

Dear Oliver:

It gave me great delight to remind you that you were responsible for Henry Cowell's writing the Set of Four for me in the summer of 1960. It received its first performance at the University of California in Berkeley on January 26, 1961. (A tape of this performance exists.) Its first New York performance took place at the Metropolitan Museum on November 30, 1962. As I write now I do not have the music before me. Along with the rest of my collection of twentieth-century harpsichord music I have given it to the library of the Yale School of Music. But I have ascertained that my registrations are noted in that copy. For the Berkeley performance I used a Challis harpsichord with sixteen, eight, eight, and four foot. For the New York performance I used a Dowd harpsichord with eight, eight, and four foot.

I never asked Henry if he so intended it, but the passages with the tone clusters always reminded me of a hymn tune played on a wheezy old harmonium. Somewhere in the piece there is a trill in octaves for the left hand which Henry put in at my special request. Along with other corresponding features I have abnormally large hands whose extensions were further increased by stretching exercises given me by a piano teacher when I was eleven or twelve years old.