Boyd has worked on recordings of Pink Floyd, Fairport Convention, Sandy Denny, Richard Thompson, Nick Drake, The Incredible String Band, R.E.M., Vashti Bunyan, John and Beverley Martyn, Maria Muldaur, Kate & Anna McGarrigle, Billy Bragg, James Booker, 10,000 Maniacs, and Muzsikás.

[3] Boyd was responsible for the sound at the 1965 Newport Folk Festival, when Bob Dylan played a controversial set backed by electric musicians.

Boyd returned to the United States at the end of 1970 to work as a music producer for Warner Bros. with special input into films, where he collaborated with Stanley Kubrick on the sound track release of A Clockwork Orange.

[9] Boyd also contributed to the soundtrack of Deliverance, directed by John Boorman, where he supervised the recording of "Dueling Banjos", which became a hit single for Eric Weissberg.

Boyd was executive producer for the 1989 feature film Scandal, starring John Hurt and Bridget Fonda about the Profumo affair in UK politics in 1963.