Audio signal transformer – easy to use with great results. The Art Dual Z Direct Dual Channel Passive DI box allows you to connect any input – line speaker instrument – and send it through an isolated balanced low impedance signal output. It has a flat and wide frequency response and can handle really high signal levels. Stuffed full of features this excellent little box allows has an input attenuator switchable low pass filters and a phase invert switch. All inside a compact and rugged box.