"Special Guest Musician" on Ring of Changes was Bias Boshell, founder member of English folk band Trees, working with Barclay James Harvest for the first time. The orchestration on "Fifties Child" and "Paraiso Dos Cavalos" was arranged by Pip Williams and performed by the New World Philharmonic Orchestra conducted by David Katz. Kevin McAlea played keyboards on "Midnight Drug" and Henry Morris provided "occasional backing vocals".[1]