[2] Aside from Neurosis, Kelly was also a member of the bands Tribes of Neurot, Blood and Time, Shrinebuilder, Corrections House, Mirrors of Psychic Warfare and Absent in Body.

[4] Kelly formed Neurosis in 1985 originally as a hardcore punk band with bassist Dave Edwardson and drummer Jason Roeder.

Kelly was also a member of the supergroup Absent in Body which formed in 2022, with Amenra's vocalist Colin H. Van Eeckhout and guitarist Mathieu J. Vandekerckhove alongside former Sepultura drummer Igor Cavalera.

Beginning in April 2011, he began hosting a monthly three hour streaming radio show on Scion A/V.com channel 5 called KMBT.

In August 2022, after admitting to abusing his wife and children, Kelly officially retired from music and public life, and his current living situation is unknown.