Radial JDI Passive Direct Box

If you’re not quite sure what a direct box is for, and why you should use one, don’t sweat it—you’re not alone. So a quick primer may be in order. A direct box—or D.I. for short—is crucial when you’re plugging an instrument straight into a mixer or DAW, as it takes the high impedance signal of a guitar, and transforms it to a low impedance, or balanced signal. Another benefit of converting to low impedance is that you can drive long lengths of cable—say, from the stage to the front-of-house-mixer—without incurring noise or a loss of high frequency response. So now do you know why a direct box is a necessity? Radial’s two new D.I.s not only provide the basics that a direct box should, they also offer a glut of other features that make them indispensable to the home recordist as well as the gigging musician. Both units are housed in rugged, almost brick-like enclosures, that are actually very elegant with their I-beam construction and baked enamel finish.
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JDI Passive Direct Box

Being a passive unit, the JDI ($200 retail/$179 street) doesn’t need a power adapter or batteries, making it perfect for plug-in-and-go operation. I simply ran the output from my piezo-equipped Taylor acoustic into the JDI’s input, connected the Thru output to my stage amplifier, and then ran the balanced XLR output to the front-of-house mixer. Done. Any phasing issues are easily nuked with the JDI’s Reverse 180 switch.

But say you dig your amp’s effects or EQ and would rather send that to the house mixer rather than your instrument’s dry-ass signal. Well, the JDI allows you to tap your amplifier’s speaker output. Simply engage the JDI’s -15dB and Speaker switches, and you can connect the unit to your speaker cab, and then run that signal straight to the board. Yum. The JDI is not a load box, however. So you need to remain connected to a speaker. The JDI also sports a Merge function, which turns the Input and Thru jacks into left/right inputs that get coupled into mono at the XLR output. This feature can come in handy when inputs on a snake or mixer are slim. Sonically, the JDI is a dream, as I encountered zero pops, clicks, or hiss. All I got was the pure sound of whatever instrument I plugged in, with no extraneous noise, and a strong, robust signal. Super sweet.

J48 Active Direct Box

So what’s the difference between active and passive D.I.s? Well, an active box requires a battery or 48-volt phantom power to operate, and Active boxes tend to be able to drive long cable runs more efficiently. The J48 Active Direct Box ($200 retail/$179 street) runs solely on phantom power and sports many of the same features as the JDI, except, the J48 offers a Low Cut switch (-6dB at 80Hz), which came in handy in slimming down my jumbo Taylor’s boomy bottom. And like the JDI, the J48 sounds blissfully clean and transparent, no matter what I plugged into it. With their unbeatable construction, and top-notch sonic properties, the JDI and J48 are must have boxes for the stage or studio. Your recordings, and your soundman will thank you.