Early bands (1997–1999) Koller played in the bands Where's Ben? and Bastian, before playing in the
grindcore band Force Fed Glass. He started playing for the band in 1997.
Converge (1999–present) Koller joined Converge in late 1999, replacing John DiGiorgio.
Kurt Ballou selected Koller to temporarily fill-in while Converge searched for a more permanent replacement for Bellorado, as he was familiar with his work in previous bands, Force Fed Glass and Blue/Green Heart, a band that Ballou and Koller played in together. After working well with the band during some local shows in Boston, Converge made him an official member. Koller's first studio release with Converge was 2001's
Jane Doe released through
Equal Vision Records.
All Pigs Must Die (2009–present) All Pigs Must Die is a heavy metal band composed of Kevin Baker of
The Hope Conspiracy and Ben Koller in addition to Adam Wentworth and Matt Woods of Bloodhorse. The former of which is also a part of Acid Tiger. All Pigs Must Die is signed to Nonbeliever Records, an imprint label of Shirts & Destroy. Their debut EP, which was recorded at Ballou's GodCity studios, was released in October 2010. In 2011, they released their first full-length called
God Is War.
Mutoid Man (2012–present) Koller recorded some songs as a two-piece band with
Stephen Brodsky of
Cave In in mid-2012 under the name Mutoid Man. The project was properly announced in March 2013, and its debut EP,
Helium Head, was released in November 2013 through
Magic Bullet Records. Describing the sound of the new project, Brodsky said, "The material picks up from where we left off with the Cave In
Shapeshifter/Dead Already cassingle, written with Ben in the band. The two of us ran with that sound and formula and took it as far as we could go." Koller and Brodsky were later joined by bassist Nick Cageao to form a three-piece band, and released their first full-length album
Bleeder on June 30, 2015, through
Sargent House. The band released their second full-length album,
War Moans, in June 2017. == Additional projects and contributions ==