Monster

Marty “Monster” Haley has been laying down bass lines since the early ’80s, drawing inspiration from legends like Geezer Butler, John Entwistle, John Deacon, Cliff Burton, Steve Harris, and early Gene Simmons—players who knew how to bring both groove and grit.

From his first U.S. tour in 1984 to charting songs in Brazil and the UK, Marty’s career has spanned decades of relentless work onstage and in the studio. With three albums, multiple U.S. and world tours, and a string of projects under his belt, he’s proven himself as both a live powerhouse and a studio craftsman.

Whether laying down punchy, show-stopping lines or keeping it subtle in service of the song, Marty’s bass always carries weight—serious punch, warmth, and low-end authority. In recent years he’s been busy ghosting in studios, co-writing, and gearing up for his next big project.