The Radial JDI MK3 Passive Direct Box is a Jensen transformer equipped, high-quality passive direct box that has the advantage of providing complete isolation for reduced noise. The exceptionally low phase distortion, almost perfect linear response, and low harmonic distortion make the JDI direct box a superb choice for recording or live performance. The rugged construction allows it to be used in abusive environments without concern. The Radial JDI Mk3 is ideal for acoustic guitars, bass, and keyboards. Considered by many to be one of the finest passive-operation direct boxes available, this Radial DI employs a Jensen isolation transformer for optimum audio performance.