Harvey Phillip Spector (December 26, 1939 – January 16, 2021) was an American record producer and songwriter who is best known for pioneering recording practices in the 1960s, followed by his trials and conviction for murder in the 2000s. Spector developed the Wall of Sound, a production technique involving a densely textured sound created through layering tone colors, resulting in a compression and chorusing effect not replicable through electronic means.
https://en.wikipedia.org/wiki/Phil_Spector