Radial Engineering PowerTube User's Guide

®

PowerTube

500 Series Tube Preamp

True to the Music

™

User Guide

®

www.radialeng.com

Radial Engineering Ltd.
1588 Kebet Way, Port Coquitlam
British Columbia, Canada, V3C 5M5
tel: [phone] • fax: [phone]
email: [e-mail]

True to the Music

www.radialeng.com

WARNING NOTICE TO USER:
The PowerTube is a high voltage tube device designed for professional use only.
Although preventative safety measures have been designed into Radial 500
series products we strictly advise against hot-swapping modules or plugging and
unplugging them when the Workhorse or other 500 series rack is powered on.
Hot swapping can cause connection sparks at the card-edge connector that could
send damaging transients to other equipment. This also greatly reduces the life
span of the contacts. Damage due to hot swapping is not covered under warranty.

There are no spare or replacement parts inside and opening the unit should only
be done by a technician familiar with 500 series modules, their operation or those
experienced at replacing tubes.

True to the Music

®

®

™

Radial PowerTube

500 Series Tube Preamp

Table of Contents Page

Overview.......................................................................................................................1

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

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

Getting Started .............................................................................................................4

Filters ............................................................................................................................5

Hidden Switches ...........................................................................................................6

Ominiport ......................................................................................................................7

Specifi cations ...............................................................................................................8

Block Diagram ..............................................................................................................8

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

Thank you for investing in a Radial PowerTube microphone amplifi er. We are very excited
about this product and are confi dent that once you get it hooked up, the excitement will be
contagious! So get ready to enjoy one of the best sounding tube preamps ever made!

Before you start revving up this vacuum tube wonder, we kindly ask that you take a few
moments to read this manual and familiarize yourself with the many features that are built in.
For instance... did you know that there is a miniature switch inside that that enables you to
safely connect up to eight PowerTubes in a Workhorse without overtaxing the power supply?
How about the hidden ground lift switch that can accidentally turn phantom power off? This
is important stuff and well worth reading!

Then, after you are done, you will likely have some questions. To address these, we invite
you to visit the PowerTube F AQ page on our web site. This is where we post the latest news
and of course questions from users. If you do not fi nd the answers you need, we invite you to
send an email to [e-mail] and we will do our very best to reply promptly.

Now get ready to tear up the airwaves with the sound of high voltage tube magic.

Radial Engineering Ltd.

PowerTube™ Preamp

®

True to the Music

Overview

The Radial PowerTube is a vacuum tube amplifi er designed to elevate the relatively low
level signal of a microphone to a +4dB professional line level. Once at line level, the signal
can then be processed by a various pieces of equipment such as compressors, limiters and
equalizers or be sent to the line level input of a recording system.

BALANCED

INPUT

Like most mic preamps, the PowerTube features common functions such as a mic input, trim
control, gain control and 48 volt phantom power. Some of the extras that are not so common
include a 10 bar LED VU meter, polarity reverse switch, a high pass fi lter and an air control
for added presence. Some of the truly unique features include the use of a premium Jensen
input transformer, fully discrete class-A output buffers and of course a select 12AX7 tube.
Together these features truly deliver more than the sum of their parts. And we are confi dent
that once you start experimenting, you fi nd the PowerTube will sound absolutely amazing in
just about any situation.

Radial Engineering Ltd.

POWERTUBE

MICPRE

Q3
EQ

TYPICAL SETUP

1

KOMIT

COMPRESSOR

PowerTube™ Preamp