Behringer Ultra-Di DI100

0dB for guitar-type pickups -20dB for line level signals Automatic switchover to battery if phantom power fails

The Radial ProD2 and ProDI (mono version) are full range passive direct boxes. Active direct boxes employ electronic circuits to change the impedance from hi-Z to lo-Z and balance the signal. Passive DI's employ a simple passive transformer to do the work. Active DI's require batteries, 48V phantom-power or external power supplies to power their circuits. Passive transformer-equipped direct boxes do not require any power to perform their task. The advantage of a transformer over typical active c