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Radial Engineering JDI Duplex Stereo Direct Box

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The Radial JDI Duplex is a full-feature, stereo passive direct box designed to enhance connectivity, reduce noise, and simplify the hectic life of th...Click To Read More About This Product

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Stereo direct box for high output sources.

The Radial JDI Duplex is a full-feature, stereo passive direct box designed to enhance connectivity, reduce noise, and simplify the hectic life of the touring professional, broadcast engineer or AV integrator. It is plug-and-play and easy to use while delivering the utmost sonic quality.

Like the Radial JDI, the Duplex employs two high-performance 'made in the USA' audio transformers and the same pristine audio signal path that has made the JDI the industry standard. It features exceptional signal handling with virtually zero phase shift or harmonic distortion, while remaining linear across the entire audio spectrum. When driven to extremes, the natural transformer saturation and resulting warm Bessel curve makes the Radial Duplex the perfect choice for smoothing out highly dynamic instruments such as digital pianos and electronic drums that can sound harsh when pushed. Transformer isolation provides the additional benefit of eliminating troublesome ground loops that can cause hum and buzz in the audio system or interfere with video displays.

This 'Swiss Army knife' DI is equipped with ¼' connectors for instruments, RCA connectors and a 3.5mm TRS for unbalanced -10dB consumer electronics plus XLR inputs for +4dB professional line sources. Radial's innovative book-end design provides protective zones on the front and rear to keep connectors and switches out of harm's way. The 14 gauge I-beam inner frame adds tremendous rigidity to eliminate outside stresses that could torque the PC board and cause premature solder joint and trace failure. The steel outer shell couples with the transformer's mu-metal shield to protect against stray magnetic fields from power transformers or lighting systems that could cause interference. Finally, a full-bottom no-slip pad works double-duty by providing both mechanical and electrical isolation. The Radial Duplex delivers outstanding connectivity, superlative audio and quiet dependable performance.

-10dB RCA connectors
+4db XLR inputs
Jensen transformer-equipped passive DI
100% isolation eliminates ground loops
Ultra linear response from 10Hz to 40kHz
Virtually zero phase & harmonic distortion
Exceptional signal handling
Eliminates hum and buzz from ground loops

Do it direct! Do it today!

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Review Snapshot

by PowerReviews
Radial EngineeringJDI Duplex Stereo Direct Box

(based on 3 reviews)

Ratings Distribution

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Reviewed by 3 customers

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(3 of 3 customers found this review helpful)


Very high-quality DI

By Marshall guy

from Undisclosed

See all my reviews

Comments about Radial Engineering JDI Duplex 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.

(2 of 2 customers found this review helpful)


A must have in your toolbox

By Stringblade

from Atlanta

See all my reviews

Comments about Radial Engineering JDI Duplex Stereo Direct Box:

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


A great little box

By Griploc

from Langley, BC Canada

About Me Professional Musician


  • Clear Sound
  • Easy To Use
  • Professional Functions


    Best Uses

    • Home Studio
    • Professional Recording

    Comments about Radial Engineering JDI Duplex Stereo Direct Box:

    I purchased this DI box for XLR input and output uses as well as the means to end the buzzing coming from my Yamaha motif xf. I was extremely amazed by the smoothness in sound and preservation in spatial imaging this little box kept in my recordings. Having Jensen transformers inside sure help bring that analog tone to the picture with my Neve DPA into the keyboard

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