DB325 is an instrument active (powered) direct box. It is designed to take a guitar, bass or keyboard and plug it directly into a computer, laptop or tablet. It can also be used to boost the signal of an instrument to be plugged in to just about anything. It is a cleanly designed simple, high end all class A way to get your instrument into different devices. Works great with piezo pickups. It will also work to add more gain to you guitar tube amp.