Born partly out of necessity and a willingness to embrace the unconventional, Matt O'Brian and the Great Blue Herons is rapidly turning into an actual band. I know, I know; it happens all the time: musicians get together, have a concept, figure out who will play what, and get a gig to ride the lightning to fame. But what grew out of a rehearsal tool quickly took a different direction and became another band entirely.

Better known as the drumming thunder in reggae giants Thunder Body, O'Brian was minding his own business when a friend in Ithaca gave him an old drum machine.

"It's really old," O'Brian says. "It's called an Ace Tone. It's a cruise ship drum machine, a one-man wedding band type thing."

Often, Thunder Body would rehearse the horns — Benton Sillick, trumpet; Abe Nouri, trombone; and Luke Norris, tenor saxophone — alone with O'Brian marking time with the rhythmic chop of his resonator guitar. They liked what they heard. And when he was offered a solo gig at the Bug Jar, O'Brian pushed to have the horns involved.

Initially, the drum machine was being used during rehearsal to learn the lines to the songs, O'Brian says, "but we never considered it a band. Thievin' Stephen asked if I could do the solo thing, and I said, 'Can I do it with the horns?'"

Two days before the gig, the group was rehearsing and they settled on the name, Matt O'Brian and the Great Blue Herons. But let's not forget about the drum machine.

"I put it through a couple of pedals," O'Brian says. "It sounds like it's under water." But O'Brian assures, while this sounds like it could be some of the dub spice and marinade Thunder Body sprinkles liberally on its own sound, it isn't.

"I kinda know what I'm doing because of that," he says. "But personally, I don't think this music is in the reggae or dub vein at all. The drum machine is just there to keep it grooving. It's got a really shitty hi-hat sound. I call it the 'splash.' It's just a metronome really. It's not like we were having trouble grooving or keeping time. That first gig, the soundman put it through a DI and it had this huge bass while I'm playing this rhythm on the guitar we call African thumb 'n' strum. There're no noisy drums or heavy bass guitar."

Conversely the band doesn't cross the street to avoid the dub and lets the music take what it needs. Seeing this band live doesn't necessarily refute what O'Brian says about the sound, but the songs do come across a bit like dub or reggae songs — or at least they do during breakdowns or bridges when the bass, keys, and the majority of the percussion breaks for a few measures only to come back in full force for drama and effect.

"This is just for the songs to sound how they want," O'Brian says, "to groove as they want. I feel people can hear the words of the song versus when you've got a 10-piece band just crushing it."

And this big little band has no specific concept.

"That's what made it so open," Sillick says. "That's what made it so fun. It just sounds cool. I don't care that I'm playing rock 'n' roll without a drum kit, without a bass player. Actually, it frees you up a little bit. When the beat isn't moving, we can stretch things a little bit more and know that the drum machine isn't going to lose one."

"It never screws up," O'Brian adds. "It really kind of gets you entranced. The horns sound regal. You're just sitting in it, 'Ah, it's so refreshing.' It's real basic."

O'Brian says it's ready for the studio. "No need at all to polish it or make it shine," he says. "It's ready to go."