The Radial SGI TX + RX Set (9V variant) is a professional instrument line driver system that allows guitar or bass signals to be sent over distances of up to 100 meters (300 feet) without noise or tone loss. The set includes the SGI-TX transmitter and SGI-RX receiver, connected with a standard balanced XLR cable.

Both units are built with Jensen transformers to deliver wide frequency response, low distortion, low noise, and a natural dynamic range. The SGI-TX uses a discrete buffered circuit to drive long cable runs, while the SGI-RX restores the original tone and impedance for the amplifier.

The 9V variant is designed for pedalboard use. Although it ships with a 15V adapter, it can also be powered with standard 9V pedalboard supplies, compatible with both center-negative and center-positive polarity. This makes it easy to integrate into modern rigs.

Typical applications include studio recording where the amp is placed in another room, live shows with off-stage isolation cabinets, and flexible routing setups with wireless or pedalboard systems—all while preserving a clean, uncolored tone.