Radial Engineering JDV MK5

The JDV Mk5 is a 100% Class A discrete active direct box that retains the original zero-negative feedback topology but adds an incredible variety of features.

The new design features two inputs, each with volume and signal presence controls and overload LEDs, as well as a fully modifiable high-pass filter to tame excessive bottom end resonance. Selection between the two inputs can be made using the AB switch on the front panel or with the addition of an optional JR2 remote control. This also allows the user to mute the output when changing instruments or mute the system between sets.

Although it can handle any type of signal, the JDV Mk5 is intended primarily for use with basses and acoustic instruments. This means that the two inputs have been optimized to handle any type of instrument, electric or acoustic, with a focus on ease of switching between instruments without losing anything!

The Input-A has Drag control for load correction that allows the artist to handle the input range from 10 K-Ohm down to 1-megaohm, an especially important feature when using a bass, because it allows the artist to replicate the 'sound and touch' as if the instrument were connected directly to the amplifier. A side access 'mic select' activates a special balanced TRS mic input for using the JDV with instruments that have condenser microphones. This 'set and forget' switch is accompanied by a 48V phantom power supply with LED indicator on the front panel. A unique safety device prevents the phantom power from turning on, preventing damage to the pickups when connecting the instrument to the wrong input. The safety device can be bypassed by changing the position of an internal jumper.

The Input-B has a load selector switch that allows you to choose between 200 K-Ohms for use with passive basses and 10-megaohm for use with piezoelectric transducers. Elevating the impedance on a piezo extends the frequency response and smooths the transient response for a more natural sound. Things get really exciting when combining the two channels. A 'blend' function on the side will allow you to combine a magnetic pickup with a piezo or mix a microphone with a pickup. The built-in Phazer allows the two audio sources to be aligned to find the sweet spot and provide what can only be described as the most natural sound ever produced by an electrified instrument.

The rear panel is overflowing with features: in addition to the two unbalanced instrument inputs and the balanced microphone input, there is a thru-put to feed an amplifier on stage. This thru-put is accompanied by a side switch that can introduce an isolation transformer into the signal path that should detect ground loops. Also included is a dedicated Tuner output to provide the performer with constant visual feedback even when the JDV Mk5 is turned off.

The balanced XLR output features 180° polarity reversal to align the phase between a PA system and the amplifier on stage or help eliminate acoustic hot spots on stage that might otherwise cause feedback. A ground-lift control will reduce hum and noise on stage caused by ground loops while a transformer in the XLR signal path can be activated to provide 100 percent isolation. When recording, the engineer will be able to choose between direct or transformer-isolated outputs or raise the output line level to a professional-quality +4dB fully balanced to feed a recorder without having to pass the signal through an external preamplifier.