Stalwart Eugene live act Medium Troy has been undergoing some changes. “We used to be a big band, sometimes as many as 11 people on stage,” says JoJo Ferreira. JoJo and his brother, Jesse Ferreira, form the core of the group. “We had tours where half the band would bail and we’d be stuck without a drummer playing four-hour sets at a taco bar in Medford.” Jo Jo Ferreira continues, “We’d just drink a whole keg on stage and pretend like we didn’t suck. It was a really fun shit show.”

Since then Ferreira and his brother have dialed Medium Troy back, focusing on the siblings’ shared love of sampled rhythms. “[We] had been making beats since we were kids,” Ferreira says. Inspired by the minimalist techno group Ratatat — who perform a sparse mix of samples, beats and live instruments — the new Medium Troy sound was born. “This mix has been really popular,” Ferreira says. “We’ve been able to tour successfully and get booked on lots of great shows and festivals. In short, we went from a mediocre but fun-to-watch eclectic, white reggae-hybrid jam band to a mix of orchestral instruments and beats.”

On Nov. 1, Medium Troy debuts an ambitious new project: The Bohemian Dub Orchestra. The Bohemian Dub Orchestra is a classical concert ensemble, accompanied by “glitchy trip-hop” beats from Medium Troy. The project is a collaboration between Medium Troy and Jeremy Schropp, resident composer at Ballet Fantastique, a Eugene-based contemporary chamber ballet company. The group’s inaugural performance will feature “interactive projection mapping,” contributions from local arts collective Harmonic Laboratory and dance performances from several local troupes.

Medium Troy plays with the Bohemian Dub Orchestra, Acorn Project and Octonaut 9 pm Friday, Nov. 1, at McDonald Theatre; $10 adv., $20 door.