User Manual

INTRODUCTION
Congratulations on your purchase of the Radial J48™ direct box.
Three years in the making, the J48™ is a unique direct box that has been
designed to handle the new generation of active battery-equipped
acoustic guitars and basses that often overload typical direct
boxes and cause distortion. Best of all, the J48 does so without
the use of batteries.
The secret is the J48’s internal digital switching power
supply that converts 48V-DC phantom power to produce
a higher internal rail voltage. This allows the J48 to
handle transients of up to 9 Volts without choking.
More dynamic headroom results in less square wave
distortion. In fact, every aspect of the J48™ design
has been optimized for maximum headroom while
introducing minimal phase, harmonic and inter-modu-
lation distortion.
But this is not all: the Radial J48 features a transformer
that isolates 48V phantom power to help eliminate
ground loops while removing hash and system noise.
This ensures that what you put in - you get out. Nothing
altered, nothing changed: just the pure and natural tone
of the instrument.
We invite you to read through this manual before using your
Radial J48 so that you can maximize it’s potential. Please log onto
www.radialeng.com for further details and updates. We also invite you
to forward any comments, questions or suggestions to [e-mail].
We love to hear from you!
Enjoy.
True to the Music
Radial Engineering J48 User Guide
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