The Steamsinger: A Bard Tinker Prestige Class (2013)

From publisher blurb:

"Look, boys, competition!" - Copper Carl of Copper Carl and the Mithril Men. What followed was one of the greatest washboard duels ever recorded on this or any other plane of existence.

Seeing music as more of a mathematical model for expression than the wondrous pulse of the world that bards are wont to describe it as, the steamsingers of the world are known for their attention to nuance and detail, intricately woven harmonies, and the fact that their roadies and backup singers are completely and totally mechanical.

The third in a series of prestige classes to be released every 50 sales of the tinker base class, the steamsinger prestige class seeks to allow the tinkers of the world to exercise both the left brain and the right brain by taking up the mantle of robo-musician. Giving up access to further innovations and greater innovations, a steamsinger appropriates the bardic performance class feature of the bard, as well as the ability to eventually teach his alpha how to perform using the master's daily performance pool. To get the rest of the automatons into the act, 27 new inventions with a musical theme give them the ability to blow out eardrums with cymbals, daze enemies with trumpets, blind with the incredibly awkward puddleflute, or sit there with a cello and eventually break the blasted thing over its knee because playing a cello is so boring.

The steamsinger's capstone ability, Solo Act, grants his alpha its very own bardic performance pool, thus allowing the alpha to act as a lead singer rather than as his backup.