Friday, September 10, 2021


 RADIAL JDX DIRECT-DRIVE, Amp Simulator and Direct Box, Street price: $199

The JDX is marketed as an amp simulator and direct box. With this as the last box in your pedalboard signal path you can effectively perform without an amplifier (provided you have some way of hearing yourself, with in-ear monitors, headphones, powered cab, etc.).

The JDX is clearly intended for guitar players. Switch controls allow you to modify the flavor of the speaker simulation applied by its circuitry. Select between Combo, Stack and 4x12. A PRESENCE switch adds a bit of extra brilliance to the tone. I’m using the STACK setting with PRESENCE set to BRIGHT.

This is an active direct box but it can not be powered by console phantom power, you must provide standard pedalboard power of 9-volts DC for this box to work. It does not come with any power supply but it’s compatible with industry standard Boss stompbox types (center negative, outer positive) and power supplies by Voodoo Lab.

In use you feed the output from a chain of stompbox effects into this direct box and it replaces the need to have an amplifier with a microphone in front of it. 


This box is easy to use and it’s hard to mess up the sound. As with anything, whether you like the quality of the sound output will depend on your application. I can see where less experienced players might not get the excitement of over 11,000 presets to explore but for actual use and recording I like the JDX a lot. It lets me focus on the notes I’m playing rather than continuously making and saving adjustments in presets. 

The sound output from this box has been heard on a lot of records. You’ll know it when you hear it. With the JDX as your amplifier, speaker and microphone you’ll need to have stomp box pedals to shape your sound. Classic effects like compressor, EQ, wah and distortion all sound great and feel natural when using the JDX as your amp destination. This is NOT a device you want to overdrive to get breakup or distortion tones, it excels at reproducing distorted tones created by other pedals, just don’t mistake it for a tube amp.

Currently I’m driving the JDX with a series pair of Joyo distortion pedals (Tauren feeding into Maximum Overdrive feeding into JDX) and I’m loving the sound of the JDX. It’s simple to use and makes distortion pedal connections to my mixing board very easy and straightforward for recording. 

I like the sound of the JDX more with distorted sounds than clean sounds. I have it installed in my Voodoo Lab switching system so I can bring the JDX in and out for preset distortion effect combinations. 



Simple settings provide easy to set tones

Uses only 40mA of current at 9-VDC so it will run on practically any stompbox power supply.

Heavy gauge steel construction provides better shielding than aluminum.


Does not run on phantom power

Not as full of a tone as boxes with Impulse Response technology inside


It took a little getting used to but after I got my sound dialed in with the JDX in the signal path it is a very satisying effect box to play and record through. I will be recording with the JDX more in the future, it makes distortion stompboxes sound good when they are connected directly into my DAW.

I look at the Radial JDX Direct Drive and I see a tool. It is not my only tool but it’s a good one. I will use it when it is appropriate for the sound. In the studio using stompboxes direct into the DAW the Radial JDX provides a missing link to achieving big fat recorded sounds, quickly.

Thanks for reading High on Technology, Good Music to You!

©2021 by Mark King, It’s not ok to quote or copy without written permission.


Power: 9VDC center negative (like Boss)

Current: 40mA

Construction: 14-gauge steel

Size: 4.75” x 3.625” x 2”

Weight: 1.6 lbs