Complete Demos is the compendium of Tally Hall's first two EP disks, Welcome to Tally Hall and Party Boobytrap, both of which were recorded in Joe Hawley's attic, along with the track "Banana Man", previously released as a single. "Good Day" won Andrew Horowitz $10,000 in the 2004 BMI Foundation's John Lennon Scholarship Competition. "Just Apathy" was named the Grand Prize Winners for Session II of the 2005 John Lennon Songwriting Contest in the pop music category.[1] In addition to Welcome to Tally Hall and Party Boobytrap, Tally Hall recorded the Pingry EP demo disk which primarily consisted of acoustic one-take demos. Several songs from the Pingry disk were re-recorded in addition to songs from Complete Demos and others to form Marvin's Marvelous Mechanical Museum.
All tracks are written by Rob Cantor, Joe Hawley, Andrew Horowitz, and Zubin Sedghi (respectively, as denoted)
Ross Federman, though credited as the drummer, does not play on this release, as he had joined after the songs were recorded.