The present invention provides, for musical instruments such as organs, action-magnets and action-magnet drivers that facilitate reduction of wiring, connections, and logic circuitry. Some embodiments of present invention provide stop action-magnets, also called SAM's, comprising integral drive circuitry and, which may further comprise additional integral circuitry. Embodiments of this invention may comprise, logic circuits such as a shift-register cells, micro-controllers, or both. Some embodiments of this invention comprise shift-cells and registers combining both SIPO and PISO functions for addressing SAM's. A single-coil SAM embodiment of the present invention may respond to signals intended to operate traditional two-coil SAM's. In another embodiment, a pipe action-magnet driver comprises logic circuitry. In yet another embodiment a pipe action-magnet comprises an integral driver that further comprises logic circuitry.