Tracklist
| 1 | Field Works w/ Eluvium – Dusk Tempi | |
| 2 | Field Works w/ Mary Lattimore – Silver Secrets | |
| 3 | Field Works w/ Jefre Cantu-Ledesma – Night Swimming | |
| 4 | Field Works w/ Machinefabriek – Kelelawar | |
| 5 | Field Works w/ Kelly Moran – Sodalis | |
| 6 | Field Works w/ Taylor Deupree – Echo Affinity | |
| 7 | Field Works w/ Noveller – A Place Both Wonderful & Strange | |
| 8 | Field Works w/ Christina Vantzou – Music For A Room With Vaulted Ceiling | |
| 9 | Field Works w/ Sarah Davachi – Marion | |
| 10 | Field Works w/ Felcia Atkinson – Night Vision, It Touched My Neck | |
| 11 | Field Works w/ JAB – Indiana Blindfolded | |
| 12 | Field Works w/ Chihei Hatakeyama – The Circle | |
| 13 | Field Works w/ Ben Lukas Boysen – Torpor | |
| 14 | Field Works w/ Stuart Hyatt, Player Piano & Julien Marchal – Between The Hawthorn & Extinction |
Stuart Hyatt returns with another sonic wonder in the Field Works series, bringing the listener into truly uncharted acoustic territory. Ultrasonic is perhaps the first ever album to use the echolocations of bats as compositional source material.
For this special double LP, Hyatt has assembled an extraordinary group of contributors: Eluvium, Christina Vantzou, Sarah Davachi, Ben Lukas Boysen, Machinefabriek, Mary Lattimore, Felicia Atkinson, Noveller, Chihei Hatakeyama, John Also Bennett, Kelly Moran, Taylor Deupree, Jefre Cantu-Ledesma, Julien Marchal, and Player Piano.
Ultrasonic is part of a broader storytelling project about the federally endangered Indiana bat. Generously funded by the IUPUI Arts & Humanities Institute and the National Geographic Society, each album contains an official printed booklet of The Endangered Species Act of 1973.