Wall of Sound is a phrase used to describe the music production techniques of legendary record producer Phil Spector. During the Wall of Sound era, Spector gathered large orchestras of musicians (even for instruments not generally used for ensemble playing such as the electric guitar) playing orchestrated parts for a fuller sound. Not so well known is that at the heart of the Wall of Sound was a basement room fitted with microphones and speakers. This room acted as an echo/reverb chamber where echo from the hard walls of the room gave his productions their distinctive quality and resulted in a full sound when played on AM radio with an impressive depth rarely heard in mono recordings.

Songwriter Jeff Barry , who worked extensively with Spector, described the Wall of Sound as:

basically a formula. You're going to have four or five guitars line up, gut-string guitars, and they're going to follow the chords...two basses in fifths, with the same type of line, and strings...six or seven horns, adding the little punches...formula percussion instruments - the little bells, the shakers, the tambourines. Phil used his own formula for echo, and some overtone arrangements with the Music. Philadelphia: Open University Press. ISBN 0335152759.