The Presys Onboard Preamp Systems are designed and built to offer maximum control, performance and quality in a small, unobtrusive format. The compact sophisticated Presys system features Volume, Bass, Mid and Treble controls, a Phase switch, and a built-in tuner with LED display. Presys preamps also include a Fishman Sonicore pickup, a low battery indicator, low profile control knobs and a unique pivot design for easy access to the battery compartment.