To Motown's stars, the four wooden steps leading down to Hitsville's basement were a bridge to a land of dreams. But to the studio musicians who shaped the Motown sound, the stairs were a gateway to a workplace, a cramped, smoke stained, dimly lit room they affectionately dubbed "The Snakepit."
For almost fourteen years on a daily and nightly basis, the musicians transformed that basement into a hit factory. They rolled masterpieces off the production line in an hour or less, trading friendly insults as they worked. Known as "Funk Brothers", they were utterly unknown.
http://www.history-of-rock.com/funk_brothers.htm