The Pro Co Sound IT1 is a compact, passive isolation transformer box designed to solve ground loop hum and buzz problems in audio signal paths. It functions by magnetically coupling the audio signal from its input to its output via a high-quality transformer, thereby breaking the direct electrical connection (specifically the ground connection) between two pieces of equipment. This eliminates the ground loop, which is a common cause of low-frequency hum when multiple AC-powered devices are interconnected, each with a slightly different ground potential. The IT1 is exceptionally simple to use, requiring no power—just connect the problematic source to its input and its output to the destination.

Housed in a rugged, palm-sized metal enclosure, the IT1 is built for reliability and durability in both permanent installations and on the road. It typically features female XLR input and male XLR output connectors, making it ideal for inserting into standard microphone or line-level balanced XLR lines. The transformer is designed for high signal fidelity, with a wide frequency response and ability to handle professional signal levels without introducing significant distortion or loss. Its passive design ensures absolute reliability and makes it immune to power failures or noise from external power supplies.

This device is an essential troubleshooting tool in the kit of any live sound engineer, studio technician, or AV integrator. It provides a quick, effective, and sonically transparent solution to one of the most persistent and frustrating problems in audio systems. By cleanly isolating audio signals, the Pro Co IT1 allows systems to operate quietly and as intended, preserving audio quality while eliminating intrusive noise.