The Uncle Klunk animatronic character and various stage props required several additional control bits on top of what was available to the standard Rolfe and Earl character, which was replaced by Klunk on stage right. This required the development of an additional system to control Klunk's stage, which would work in tandem with the standard Gray Box in the Rock-afire Explosion Control System.
Having internal 5V and 24V power supplies and not requiring any interface to the rest of the show other than receiving a feed of the top drawer data from the main tape deck, the Uncle Klunk Controller was essentially a self-contained system. It contained two main circuit boards, the Computerized Tape Reader Board (similar to a playback board, but enhanced with a microprocessor), and the 32 output driver board (analogous to standard Pianocorder driver boards, but functionally different). According to the Klunk installation tape, the controller supported 30 outputs, divided into two connectors to which the ribbon cables from the valves were connected. Rolfe and Earl's control bits were recycled, with the remaining 8 bits being taken from the normally unused bits in the typical Rock-afire Pianocorder-based data format.