The Crystals are an American girl group that was particularly prominent in the early 1960s. Known for their pop-oriented R&B sound, they were one of the defining acts of the Phil Spector-produced "Wall of Sound" technique, which used dense, layered arrangements to create a rich, distinctive sonic backdrop. The group's most notable members included Dee Dee Kenniebrew, who remains a member to this day. With influential hits like "Da Doo Ron Ron" and "Then He Kissed Me", The Crystals have left a lasting imprint on the landscape of pop and R&B music.