The Penumbra Music Collection spans from its inception in 1994 until
2015 and covers commercial, beta, and live recordings of the label as
well as administrative records.
The ESS Collection is a continually expanding collection of all of ESS's programs and projects since its inception in 1986.
The Sun Ra/El Saturn Collection consists of approximately 600 tapes dating from the 1950s-1993 that represent the work of iconoclastic composer and bandleader Sun Ra.
The Malachi Ritscher Collection represents the work of Chicago sound recordist Malachi Ritscher. Ritscher was a passionate supporter of Chicago's improvised music jazz scene.
The (a)R(t) Noise / Necessary Arts Collection consists of 33 music CDs with different assortments of musical arrangements and including a diverse amount of musicians and instruments. The collection represents the work of Milwaukee writer, sound and visual artist, and life-long entrepreneurial scholar Thomas Gaudynski.