The Radial Engineering ProDI is a high-performance passive direct box that delivers pure, noise-free signal for live and recording applications. The ProDI employs a custom-made transformer to convert instrument impedance, eliminating ground loops and ensuring the highest quality signal transfer. Linear frequency response from 20Hz to 18kHz means zero coloration of your tone. Simply plug in your instrument via the 1/4" input and thru jacks and send a balanced signal to the mixer or interface via the XLR output.