Phil Spector
Phil Spector is a convicted murderer. Before that, he was an influential music industry figure best-known for his work with the behind the "girl groups" of the early 1960s and with the Beatles. He is credited with inventing the so-called "Wall of Sound".
The concept behind the Wall of Sound was that the sound of an instrument could be enhanced through the recording of several instruments (and possibly additional sounds) at the same time. This became integrated into the concept of modern multitrack recording - unlike a live performance, the instruments on most studio albums are played separately into mixable and modifiable "tracks."
Spector would become violent when drunk. After a six-year legal battle following the death of actress Lana Clarkson, he was found guilty of second-degree murder in 2009.