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Radial Engineering JDI Duplex mk4 Stereo Direct Box  

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  • -10dB RCA connectors
  • +4db XLR inputs
  • Jensen transformer-equipped passive DI
Description & Specs
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    - $25.01
  • Your Price:
1 Used From $307.99

Order Now! Expected to ship 05-06-2014

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Radial Engineering

It just might be the world's finest direct box.

Now with dual -10dB RCA connectors and dual +4db XLR inputs. Passive DI employs a Jensen isolation transformer for optimum audio performance offering outstanding linearity at all frequencies, combined with extraordinary level handling without introducing distortion. The completely passive plug & play JDI does not require any power and has the unique advantage of eliminating 60-cycle ground loops. This makes it a definite favorite with informed audio engineers. Great for guitars, bass, and keyboards and particularly adept with high-output, broadband instruments such as active instruments and digital keyboards. May be rackmounted using the J-RAK Adaptor (not included).

Housed in a 14 gauge steel welded I-beam chassis, it protects all connectors and switches with a unique book-end design. The input panel is equipped with a pair of 1/4" and RCA inputs and thru-puts. A unique Merge function provides passive mix to convert the in/thru routing into a stereo-to-mono mix function--a valuable channel saver for large keyboard rigs and multiple audio sources. Each channel is also outfitted with a 10kHz low-pass filter to eliminate high-frequency system noise and a 15dB pad for greater source control. A switch on each channel allows the user to select the XLR male input. This simultaneously introduces a 20dB pad to allow high output +4dB line level devices to interface into snake systems and splitters without requiring an external attenuator. The rear panel features the XLR inputs and outputs along with polarity reverse and ground lift.


  • -10dB RCA connectors
  • +4db XLR inputs
  • Jensen transformer-equipped passive DI
  • 100% isolation eliminates ground loops
  • Virtually zero phase & harmonic distortion
  • Exceptional signal handling
  • High common mode noise rejection

Do it direct! Do it TODAY!

Customer Reviews

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by PowerReviews
Radial EngineeringJDI Duplex mk4 Stereo Direct Box

(based on 2 reviews)

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Reviewed by 2 customers

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(1 of 1 customers found this review helpful)


A must have in your toolbox

By Stringblade

from Atlanta

Comments about Radial Engineering JDI Duplex mk4 Stereo Direct Box:

Very clean. Built very well, (also heavy). A must have.

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(2 of 2 customers found this review helpful)


Very high-quality DI

By Marshall guy

from Undisclosed

Comments about Radial Engineering JDI Duplex mk4 Stereo Direct Box:

For critical recording or live sound work, this DI is excellent. It may seem odd, but the best thing about this DI is that you can't hear it! (What you put in, you get out; nothing added, nothing taken away.)It is very clean and warm without ANY noise or tone coloration. I use it primarily for direct connection of bass and guitars for live sound in a "low stage volume" environment and it works very well.

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