he Model 4 is specifically designed to be wired with a separate pickup, so that both the 2Mic and pickup signals (separate) can exit the guitar via the single Model 4 output jack. But, the Model 4 can function OK as a “microphone only” system. Adding a pickup is optional… not required. The Model 4 is powered by a single 9v battery mounted on its own supporting arm and suspended inside the body of the guitar. Installation instructions are included.
If another pickup is added, wiring options are included for installing the additional pickup if it also uses a battery