Steven Shane McDonald (born May 24, 1967) is an American rock musician, best known as the bass guitarist in the Los Angeles alternative rock/power pop band Redd Kross. He is also a member of the hardcore punk band Off!, which formed in late 2009. McDonald has appeared in numerous film projects with his older brother Jeff McDonald including: the 1984 film Desperate Teenage Lovedolls and its sequel Lovedolls Superstar; and the 1990 film Spirit of '76.
McDonald produced an album by The Format, Dog Problems, on which he played bass and sang backup vocals on a few tracks. He later produced, engineered, and mixed fun.'s debut album, Aim and Ignite, as well as performing as a bassist and backup vocalist on some of the songs. He was also one of the various band members on the original Tenacious D album, along with Dave Grohl; keyboardist Page McConnell of Phish; guitarist Warren Fitzgerald with band frontmen Jack Black and Kyle Gass. He appeared with Tenacious D on MADtv playing "Lee" and "Tribute". He also featured in the band Trainwreck on bass.
In the summer of 2002 he became so excited about The White Stripes' new album, White Blood Cells, that he recorded bass lines to two songs of the typically bass-less duo's work. The New York Times, Entertainment Weekly and other outlets reported on it and due to overwhelming demand he added bass to all of the songs, posted the new creation online, and allowed people to download the tracks for free. He called it an art project named Redd Blood Cells which reached a peak of 60,000 downloads in a single day, causing the server to crash from the traffic.
In 2016, it was announced that McDonald would be joining the Melvins. He recorded four songs with the band, which were released as an EP titled War Pussy, later to be included on the album Basses Loaded. Their first full release with McDonald, a double album titled A Walk with Love & Death, was released on July 7, 2017.
Steven is married to That Dog vocalist Anna Waronker. During the summer of 2007 Steven began using the nickname "Mr. Urbane." But during the summer of 2009, Steven insisted on being referred to as "Dr. Swaddles."