In 2008 Rochester audiences seemed to fall under the spell of one particular movie star, a dusky, nine-foot-long beauty called L1037. The acclaimed documentary that chronicled the life of this Steinway concert grand from forest to stage played to billions of people (give or take billions) in its handful of presentations at the Dryden that year, and "Note By Note: The Making of Steinway L1037" returns this Saturday for a long-awaited encore, this time with director Ben Niles in tow for a Q&A following the screening. Now, you probably wouldn't diagnose this music-crazy town as having been in the throes of pianomania back then, but I might, and with apologies for such blatant corniness. It's only because I could really use a segue.

A fitting companion piece to "Note By Note," the absorbing "Pianomania" is another one of those documentaries that focuses on an important job that gets done even though very few stop to think about the skilled individual who devotes his time and energy to doing it. So meet Stefan Knüpfer, a boyish, bespectacled piano technician with Steinway & Sons. Knüpfer is Steinway's man in Vienna, in charge of fine-tuning the pianos played by the world-class musicians who visit Mozart's later-life stomping grounds. And I do mean "fine-tuning"; we watch as Knüpfer meticulously caters to the precision musical demands of classical-music luminaries like Lang Lang, Alfred Brendel, and Pierre-Laurent Aimard, with much of "Pianomania" devoted to Knüpfer's quest to get the sound exactly right for Aimard as he prepares to record Bach's "The Art of Fugue" in Vienna's Konzerthaus.

As Steinway's clients put Knüpfer through his paces, often with a tonal specification no more explicit than "magic," it's hard not to be a little awed by Knüpfer's professional patience while he makes the tiniest of adjustments, barely detectable to our lay-ears, upon instruments that are nonetheless at the mercy of conditions like humidity and temperature. And each piano has its own unique tone, which Knüpfer must keep mentally catalogued to meet the requirements of the various musicians. Directors Robert Cibis and Lilian Franck don't give us too many personal details on their subject - we know he has a cute dog as well as a wife who bakes a decent cheesecake - but we do get glimpses into his amiable personality and seeming make-it-happen unflappability, even in the face of requests that are nearly impossible to inarticulate and possibly impossible period.

Unsurprisingly a gifted pianist in his own right, albeit one with no wish for the limelight ("I can get off stage when the public comes in," Knüpfer says), the Master Tuner derives obvious pleasure from the classic job well done, and witnessing his wide-eyed delight as he brainstorms outrageous possibilities for piano and violin with the musical comedy duo of Aleksey Igudesman and Richard Hyung-ki Joo is a treat for us as well. "Pianists are mostly dissatisfied," Knüpfer confides to us of his challenging clients, but their eventual satisfaction takes the form of admiration and a little bit of wonder at the calm, attentive man who consistently manages to construct that crucial bridge between science and art