There are good reasons why many music groups are comprised of siblings and family. Believe me, I know; I’ve been in a duo with my brother for nearly fifty years. Playing music together as adults is a natural outgrowth of games shared in childhood. Enduring the rigors of touring is easier with people you’re used to living with in tight quarters. In a business not known for high ethical standards, being able to trust your partners around money is a big plus. When it comes to distributing the tasks involved in managing a group, knowing each other’s strengths and weaknesses helps. (It’s easy to agree that the sibling who was awful with math in school should not maintain the books.)

Then there are the musical reasons. This is especially true for singers, who start out with the advantage of having genetically similar instruments, which eventually manifest as naturally homogenized harmonies. Long before they decide to turn pro, they’ve already put in years of informal rehearsals, singing around the piano, or bowing, picking, and strumming in the living room and around backyard campfires.

Which brings me to the Oshima Brothers, Sean and Jamie, a young duo who are beginning to tour widely from their home base in rural Maine. Talk about hereditarily enhanced harmonies–their eerily similar voices blend seamlessly throughout their ranges, from their smooth tenors to their high falsettos. Their years of making music together are evident in pronunciation so identical, phrasing so tight, that you think you’re listening to masterful overdubbing rather than to two distinct voices. And they’ve staked out their territories, musical and other, efficiently and effectively. Sean, three years older at twenty-four, is the duo’s songwriter and rhythm guitarist. His haunting, ethereal melodies support lyrics that run the gamut from plain spoken (“With music we’re escaping from the everyday, dancing on the weekend, leaving it all behind, dancing when we know we should be sleeping, but we will sleep after we die”) to poetically mysterious (“She’s a nine-mile kite, stitched with dynamite”).

Jamie plays expert electric guitar, drums, keyboard, and more instruments than he has fingers to count them on. By adding octave pedal, foot percussion board, looping, and other effects, the brothers create an unexpectedly full and varied sound for their live shows.

The Oshima Brothers will play the Ark’s Stage on Main on Saturday night of the Art Fair, July 20. If you brave the heat, the thunderstorms, the crowds, and all the other pleasures of the Art Fair, you’ll be able to brag that you heard their first Ann Arbor show.