The Righteous Brothers’ 1965 recording of “Unchained Melody” became an enduring hit despite being issued as the B-side to “Hung On You”. The article says the duo used the less closely supervised B-side process to work outside producer Phil Spector’s control, with Bill Medley producing and Bobby Hatfield delivering the lead vocal; its success helped demonstrate their independence from Spector.

Radio DJs reportedly preferred “Unchained Melody” and played it instead of the intended A-side, turning the older song into a major hit. Hatfield won the lead-vocal role by an alleged coin toss, while Medley retained a high vocal passage Hatfield wanted to re-record; Spector was later credited on some pressings despite reportedly having little involvement. The song returned to the charts decades later, reinforcing its status as a classic ballad.