On Saturday, the avant-garde duo Bluebrain held their final Boombox Walk at the U.S. Botanic Garden. Among the welcoming greenery and flowers, Ryan and Hays Holladay organized the group of participants, handing everyone who had RSVP’d their respective cassettes, CDs and MP3 files. On their signal, everyone pressed play and walked around the garden en masse, creating a huge, mobile orchestra.

Bluebrain is bringing back their old Boombox Walk one last time tomorrow. Ryan Holladay, one half of the experimental duo, talks about retiring the event in style.