Following spelling bee champs, crossword puzzle enthusiasts and many more, practitioners and fans of barbershop quartet singing become the latest members of a competitive subculture to go under the documentarian's microscope in American Harmony.

Following spelling bee champs, crossword puzzle enthusiasts and many more, practitioners and fans of barbershop quartet singing become the latest members of a competitive subculture to go under the documentarian's microscope in American Harmony.

Director Aengus James spends three years with a handful of quartets from around the country, most seeded to win or place in the annual International Championship of Barbershop. If one dominates the screen time, it's barbershop super-group Max Q, particularly Jeff the arrogant veteran and Tony the grown-up prodigy.

Tony's incredibly nice, as are the singers in elder comic ensemble Reveille and young, fast-rising OC Times, though it's a little creepy when they cap a discussion of their sex-symbol status on the barbershop circuit by serenading a random waitress.

But for the purposes of a documentary genre that feeds on passion, these guys are too nice, and when they do succumb to moments of bitterness or rivalry, James quickly moves on.

Between the playing down of drama, the playing up of heavily worked, acquired-taste harmonies and a near total void of historical context for a subject that could've used some, this can be a tough one for the uninitiated.