The Zdirect Professional Passive Direct Box is a high-quality interface that lets you connect instrument, line, or speaker-level signals to a mixer or other balanced input through a high-performance audio isolation transformer. The high-impedance, single-ended 1/4" input is converted by the transformer into an isolated balanced low-impedance signal output. Extremely flat and wide frequency response with high signal level handling. The ART Zdirect delivers clean and neutral sound with a wide variety of signal sources and over long signal runs in otherwise high-noise , live sound environments.