Radial Engineering JDI Passive Direct Box (JDI)

Radial Engineering JDI Mk3 Passive Direct Box with Jensen Transformer and Ultra-Low Distortion Signal Handling

The Radial Engineering JDI Mk3 is a world-standard passive direct box designed for pristine audio signal conversion in professional live sound, studio recording, and broadcast applications. Built around a premium Jensen transformer, it delivers exceptionally low distortion, extended frequency response, and superior phase accuracy, ensuring your instrument tone remains natural and uncolored.

Engineered for acoustic guitar, bass, keyboards, and other line-level sources, the JDI Mk3 provides reliable impedance matching and balanced output conversion for clean transmission over long cable runs. Its passive design requires no external power, making it extremely dependable in any environment while eliminating noise and power-related issues.

The Jensen transformer at the heart of the JDI Mk3 is known for its transparency and headroom, allowing it to handle high signal levels without saturation while preserving detail and dynamics. A built-in ground lift switch helps eliminate hum and ground loop noise, ensuring consistent, quiet operation on any stage or studio setup.

Housed in a rugged 14-gauge steel enclosure with internal I-beam construction, the JDI Mk3 is built to withstand years of touring abuse while maintaining its industry-leading performance.

Key Features:

• Premium passive direct box with Jensen transformer

• Ultra-low distortion and extended frequency response

• Exceptional headroom for clean, transparent signal handling

• Designed for acoustic guitar, bass, keyboards, and more

• Passive operation—no power required

• Ground lift switch for hum and noise reduction

• Maintains natural instrument tone and dynamics

• Heavy-duty 14-gauge steel chassis for maximum durability

• Industry-standard DI for live, studio, and broadcast use