[12][13] In April 2019 he co-curated the festival Neo-Pastiche: Changes in American Music at Black Mountain College Museum + Arts Center in Asheville, NC, which featured performances by Eugene Chadbourne, Jeff Witscher, Petr Kotik, the S.E.M.

Ensemble performing pieces by Julius Eastman, Morton Feldman, John Cage plus other contemporary experimental artists.

After over a year of bicoastal collaboration, in 2019 at an evening-length concert of their works at ISSUE Project Room[16] Callahan & Jeff Witscher performed their large collaborative piece What Happens on Earth Stays on Earth: Taking the familiar Q&A format as its basic form, the piece functions as an expanded generative interview between multiple speakers — both human and technological — as an unhinged, overlapping narrative of contemporary life.

Begun in 2017 as an idea, WHOESOE consists of a series of prompts given to a selection of interviewees (Madalyn Merkey, Asha Sheshadri, Colleen O’Connor, Nihal Ramchandani, Daren Ho, and Josh Haringa) whose responses are recorded.

Their music has been described as "disturbing and ridiculous, but a force to be reckoned with"[19] and "[h]yper-disorienting... [having] a playfully disruptive and irreverent attitude and aptitude for dis/jointed sound.