Phil Spector’s Wall of Sound masterpiece, “You’ve Lost That Lovin’ Feelin’,” took over 39 takes and $35,000 to create, featuring The Righteous Brothers, Cher, and The Wrecking Crew. The result? A four-minute epic that rewrote the rules of pop music and left even its creators doubting it would be a hit—until it became the most played song on U.S. radio in the 20th century.