If you thought System of a Down's second album, Toxicity, was brain-frazzlingly eclectic, wait'll you catch an earful of the LP vocalist Serj Tankian is currently working on with Armenian multi-instrumentalist Arto Tuncboyaciyan.

"It's very experimental and pretty universal," the singer said Thursday from his Los Angeles home. "There are influences in there from China, Japan, Africa, Jamaica, Europe. But it's not only world music, there's jazz and a little hip-hop and rock and dance. There's a song that uses poetry with flute and with birds singing in the back. Then there's a drum'n'bass-type song with tablas and horns and strings. There are a lot of different flavors and colors."

Tankian plans to release the as-yet-untitled disc next summer on his label Serjical Strike. He said the record will feature 15 tracks and an intro. And while he and Tuncboyaciyan have recorded most of the music, there are practically no lyrics — largely because Tankian opted to scat, not sing, his vocal parts.

"A lot of the vocals have these almost tribal truths that can be understood by any language or tradition or culture," he said.

Unlike the music of System of a Down, which is painstakingly pre-planned, the songs Tankian recorded with Tuncboyaciyan were largely improvised on the spot during two sessions, one last month, the other in August.

"It was really refreshing to make music that was so improvisational," Tankian said. "That's where I had the most fun, because everything was on the spot. We just went with whatever stream-of-consciousness ideas came out and I believe in that as an ultimate technique of truth sometimes."

Tankian first met Tuncboyaciyan at last year's Armenian Music Awards, where the multi-instrumentalist was creating flute sounds with a Coke bottle while banging polyrhythmically on a tambourine. Tankian was so impressed by Tuncboyaciyan's performance he invited him to work on Toxicity. Tuncboyaciyan recorded an outro after "Aerials" and a mid-section in "Science," and during the recording sessions, he and Tankian became friends.

The two didn't consider working together, though, until a mutual friend suggested they collaborate. Also helping out on the record is System of a Down bassist Shavo Odadjian, who contributed DJ loops and scratches to the project.

"People don't realize it, but he's a DJ as well. So he did some tracks on two of the songs and I mixed them and cut them up. It was really fun to do and it came out really great."

For a feature interview with System of a Down, check out "System Of A Down: Toxic Avengers."