Brett Nelson (born 1969) is an American multi-instrumentalist, singer and songwriter best known as the bassist for the indie rock band Built to Spill.In high school, Nelson played in a band called Farm Days along with Doug Martsch and Andy Capps. Nelson's next band, Butterfly Train, released two albums on Up Records, in 1994 and 1996, before breaking up. (Capps was drummer for the latter album.)In 1994, Nelson and Capps joined Martsch's Built to Spill. Nelson has appeared on every album except the debut, Ultimate Alternative Wavers.Nelson sings and plays guitar and keyboards for The Suffocation Keep, which released its debut album John Hughes Was Never So Wrong in 2002.