Ronald Clements Malo was an American engineer for Chicago's Chess Studios from 1959 until 1970. He was the engineer for the first sessions the Rolling Stones did in the US, in Chicago in June 1964, recording songs that wound up appearing on the albums 12 X 5, The Rolling Stones, Now! and December's Children . He was also the engineer at Chess when they returned in November 1964 to do more sessions there, and when they came back a third time in May 1965.