Talking to Trey Spruance, the mad scientist behind Secret Chiefs 3, is a total mind trip. Although he speaks casually about such technical matters as modal theory, dastgah tunings and tetrachords, the music of his unusual band is, at bottom, hard-hitting instrumental rock with a twist.

Secret Chiefs 3 plays Neumos on Wednesday on a double bill with Dengue Fever.

Spruance's group combines Persian scales, tunings and rhythms with elements of metal, surf rock and electronic music to form a postmodern mishmash of folk psychedelia. You might hear a wailing electric rebab (Middle Eastern fiddle) gliding above distorted guitars, anchored by rock drums thrashing out uneven rhythms.

Spruance, formerly of Faith No More and Mr. Bungle, formed Secret Chiefs 3 on a mission to rediscover musical dimensions he felt had been forgotten in the West.

"If there are fundamentals that are shared between musical cultures, I'm hoping that I'm touching those fundamentals," he says over the phone.

Spruance almost gags when he hears his music described as "otherworldly."

"It's very immediate," he insists. "We talk all this heady sounding theory, but basically the music kicks your ass. When you hear it, you feel more like you want to dance than sit around stroking your beard about it."

The Neumos show has a global vibe. Co-headliner Dengue Fever will surely delight with its shiny brand of Cambodian psychedelic surf-pop. The two bands go way back. Both had members in the 1990s rock group Dieselhed, and Spruance produced Dengue Fever's self-titled first album. Spruance reveals that there might be collaboration between the bands at Neumos, which could make for some memorable moments.

On some level, Secret Chiefs 3 could be seen as just another example of Westerners ripping off world music in order to sound different. Yet Spruance invests a lot of time learning about the traditions he borrows from. Accomplished players of Middle Eastern music such as April Centrone of the New York Arabic Orchestra and Iranian percussionist Shamou are open to collaborating with Secret Chiefs 3.

Decide for yourself whether this band takes too much from afar in creating its sound. Regardless, their set promises to be a loud, trance-y mesh of carefully crafted instrumental rock.

Claire Connell: clarconnell@gmail.com