Radial Engineering JDI Stereo User's Guide

jdi stereo user guide
jensen transformer equipped
passive direct box

Radial Engineering Ltd.
1588 Kebet Way, Port Coquitlam BC V3C 5M5

Tel: [phone] • Fax: [phone] • Email: [e-mail]

radial jdi stereo passive direct box
user guide

Introduction ....................................................................................... 1

JDI Stereo Features ......................................................................... 2

Making Connections ......................................................................... 3

Using the PAD .................................................................................. 4

Using the Ground Lift........................................................................ 4

Passive vs. Active ............................................................................. 5

Understanding Loading .................................................................... 6

Optional Mounting Accessories ........................................................ 7

Specications ................................................................................... 8

Block Diagram .................................................................................. 9

Radial Limited Warranty ...................................................Back Cover

Thank you for purchasing the Radial JDI Stereo. This marvelous passive direct box employs two great sounding Jensen
transformers to convert the impedance and balance the signal. Jensen transformers are legendary in their ability to transfer the
minute details of your most cherished instrument and gracefully handle transients without choking. This makes the JDI Stereo
a very effective DI box for all types of instruments.

The JDI Stereo is in fact a very easy to use direct box that is purposely made to be compact and quick to deploy. You simply
plug in and it works. No power required. There are however some great features that are built in that should be understood in
order to get the most out of your JDI. So please take a few minutes to go through this user guide to ensure you get the most out

of it. If after you have read it, you nd yourself asking questions; please visit the FAQ section on the web page. This is where
we post updates and questions from users. If you still do not nd the answer or need further clarication, we invite you to send

us an email at [e-mail] and we will do our very best to reply in short order.

Now get ready to enjoy what can only be called the best sounding passive direct box ever made!

Radial Engineering Ltd. JDI Stereo™ Direct Box User Guide

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FEATURES

1. -15dB PAD: Reduces the input sensitivity of the left
channel to prevent overload.

2. ¼” INPUTS: Left and right unbalanced, hi-Z inputs used
to connect instruments.

3. ¼” THRU-PUTS: Left and right parallel outputs used to

connect the hi-Z instrument signal to an amplier, tuner

or personal monitoring system.

4. -15dB PAD: Reduces the input sensitivity of the right
channel to prevent overload.

3

5. I-BEAM REINFORCED: 14-gauge steel enclosure with
rigid I-beam construction makes it impossible to torque
the PC board and cause solder joints to go cold.

6. BOOKEND DESIGN: The bookend design creates a
protective zone around the switches and connectors.

7. XLR OUTPUTS: Left and right balanced, low-Z mic-level
output. Wired to AES standard pin-1 ground, pin-2 hot
(+) and pin-3 cold (-).

8. GROUND LIFT: Disconnects pin-1 at both XLR outputs
to reduce hum and buzz caused by ground loops.

9. FULL BOTTOM PAD: Isolates the DI from the amp
chassis and keeps it from sliding around on busy stages.

Radial Engineering Ltd. JDI Stereo™ Direct Box User Guide

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4 5

OVERVIEW

The Radial JDI is a passive direct box. This means that it does not require any power to make it work. You simply plug in and it
will quietly go to work. Further, as the JDI Stereo employs transformers, these naturally block stray DC voltage that can cause
system noise. This also means that 48V phantom power as used with condenser microphones will not harm the JDI Stereo.

MAKING CONNECTIONS

As with all audio gear, always ensure audio system levels are turned down or equipment turned off before making connections.
This will avoid plug-in or turn-on transients from damaging more sensitive components such as tweeters.

There are two channels on the JDI Stereo. These are identical and feature a ¼” INPUT, a ¼” THRU-put and a balanced XLR
out. Connect your source instrument to the input and the balanced XLR out to the PA system or recorder. The THRU connector
provides the means for connecting the instrument to a stage amp or personal monitor system. Simply connect the THRU to your
amp or monitor. Unbalanced cables are much more susceptible to noise than their balanced counterparts. Keeping unbalanced
cables under 8 meters (25’) in length is good practice while balanced cables can easily extend 100 meters (300’). The balanced
output of the JDI Stereo is mic level, meaning that it should be connected to the mic input of a mixing console or mic preamp.

Amp

Thru Thru

Input

Using the JDI Stereo with a bass and stage amp

Radial Engineering Ltd. JDI Stereo™ Direct Box User Guide

Balanced Outs Balanced Outs

Inputs

JDI Stereo with a keyboard, mixer and powered speaker

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MonitorsSub-Mixer