Most battery-powered guitars and basses will produce as much as 7 Volts when played at maximum volume, which can easily overload typical active direct boxes which have are only able to handle about 3 Volts. The J48 uses a unique switching power supply that raises the internal rail voltage so it can handle up to an incredible 9 Volts, resulting in improved signal handling and greater headroom. This additional headroom significantly reduces distortion of all types, allowing the natural tone and character of the instrument to shine through.