Radial Engineering 1100, 1102 User manual

www.radialeng.com

PRO DI

Direct Box

PRO D2

Stereo Direct Box

User Guide

Radial Engineering
1638 Kebet Way, Port Coquitlam BC V3C 5W9 tel: [phone] • fax: [phone]
email: [e-mail] • web: www.radialeng.com

PRO DI AND PRO D2 USER GUIDE

TABLE OF CONTENTS PAGE

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

Features ..................................................................................2

Making connections .................................................................3

Re-amping with the PRO DI ....................................................4

Frequently asked questions ....................................................4

Block diagram and specifications ............................................5

Warranty ....................................................................Back cover

This manual covers the single channel PRO DI and the stereo
two channel PRO D2. As both devices are virtually identical, this
manual will discuss the PRO DI.

WELCOME

Congratulations on your purchase of the Radial PRO DI or PRO D2 direct box, one of the most versatile and useful pieces
of equipment you will likely ever own! Why do we say this? Simple: a good passive direct box can often find its way into
all kinds of applications and be a real problem-solver for both live PA systems and studio recording. For example, the PRO
DI can be used to eliminate noise, split signals, convert unbalanced lines to balanced, and can be used backwards to send
pre-recorded signals to a guitar amp for an effect called re-amping.

As with all Radial products, every attempt has been made to make the PRO DI ‘plug & play’ easy-to-use. However, it is still
a good idea to read this manual thoroughly to ensure you take full advantage of all the features that are built-in, so that the
results you get are the very best possible. Should you have any questions on your new PRO DI, please consult the Radial
website FAQ section, as this is where we publish questions and answers from users after a product has been released. If
you do not find the answer you are looking for, please feel free to send us an email at [e-mail] and we will do
our very best to get back to you promptly.

Now plug in the ol' Martin, turn it up, way up… and enjoy!

Radial Engineering Ltd.
1638 Kebet Way, Port Coquitlam BC V3C 5W9
tel: [phone] • fax: [phone]
email: [e-mail] • web: www.radialeng.com

True to the Music

INTRODUCTION

The Radial PRO DI is a passive direct box. This means that unlike active direct boxes that either require a battery or power
of some sort to make them work, your PRO DI does not need any power at all. It is ‘plug & play’ easy-to-use.

A direct box is primarily used to convert a high impedance instrument signals
to a low impedance balanced mic-level signal, which can then be
processed like a microphone and driven through long cables without
introducing noise. The PRO DI employs a high quality impedance­matching transformer to do the conversion.

Typical applications for the PRO DI are connecting electronic
instruments like guitar, bass, keyboard, and drum machines
directly to a PA or recording system. Because the output of
the PRO DI matches that of a typical microphone, the PRO
DI is perfectly suited for use in live sound and recording stu­dio systems where microphone signals are put through long
cable systems to a mixing console and where all signals are
balanced to keep noise down.

The cool thing about transformers is that they not only stop noise
caused by ground loops, they can be connected to work in both
directions! In other words, your PRO DI can convert a hi-Z unbalanced
input to a low-Z balanced microphone signal (typical use) or it can do it in
reverse and convert a low-Z balanced microphone signal to a hi-Z unbalanced
output. Connecting the PRO DI in reverse, you could for instance, take the balanced
output from a mixer and send it to a DVD recorder for proper impedance and level matching, or take a pre-recorded track
from a digital workstation and send it to a guitar effect pedal for re-amping effects. A good passive DI can be used to inter­face all kinds of audio equipment and can solve many impedance and noise problems.

Radial Engineering PRO DI User Guide

1