The RJM MultiBox is a multi-function MIDI interface designed as a central problem solver for complex rig architectures. It functions simultaneously as a MIDI Thru box, TRS MIDI converter, and bidirectional converter to seamlessly bridge devices with varying connection standards. Additionally, it serves as a phantom power adapter, combining power and MIDI signals for Mastermind controllers over a single 7-pin cable. Internal jumpers allow for individual configuration of the four TRS outputs (Tip-Active, Ring-Active, or Standard) to suit brands such as Strymon, Boss, or Chase Bliss. It is a dedicated routing solution designed for maximum compatibility within MIDI ecosystems. The compact enclosure is built for discreet mounting under pedalboards or within rack systems.