This project provides open-source firmware and hardware designs to replace the original ROM cartridge in Ye Merrie Minstrel handheld bell units. Using ESP-NOW wireless communication, multiple sets of bells can be synchronized to play together in a choir. The PCB is meant to be a direct drop-in replacement to the original ROM cartridge, no modifications of the device is required. I reccomend a power adapter with a larger current capacity than the original 200mA to compensate for the extra power comsumption of the ESP32.