Radial Engineering SGI44 Users Manual

RADIAL SGI-44 BALANCED GUITAR INTERFACE

When used in combination with the JX44 the optional SGI-44 can either be used
as a bi-directional long haul effects loop or as a single ended driver from a guitar
to the JX44 and your amps. Balanced audio connections between the JX44 and
SGI-44 allow distances up to 100 meters (300 feet) using standard XLR mic cable.
This is accomplished using a proprietary hybrid active drive circuit with Jensen
transformer isolation to transfer the signal between units without introducing noise
or signal loss.

A recessed DRAG control is provided at the SGI-44 input allowing for the most
natural tone when driving the JX44 directly from a guitar. As an added convenience,
the SGI-44 is equipped with a buffered tuner output. Connecting your tuner here
will remove it from your signal chain to prevent digital clock noise from bleeding
into your guitar sound.

HOW IT WORKS

When active, the SGI LOOP on-board the JX44 is global to all instrument inputs.
The SGI interface converts instruments to a proprietary balanced low impedance
signal. The converted signal is then output at the TX (transmit) jack on the back
of the JX44.

The SGI-44 receives the signal at its RX (receive) jack and converts it to
unbalanced high impedance for connection to effect pedals. The hi-Z output from
the pedals is connected back to the SGI-44 where it is re-converted to a balanced
low impedance signal and returned to the JX44 to complete the SGI LOOP
(Fig.35). In the block diagram below you can see the SGI LOOP is inserted in the
signal path after the inputs and before the local EFX effects loop.

JX44

INPUTS

A THRU D

True to the Music

Fig.35 - The complete SGI LOOP.

SGI TX
SGI RX

SGI LOOP

EFX SEND
EFX RECV

AMPLIFIER OUTPUTS

1 THRU 4

LOCAL

EFX LOOP

USING THE SGI-44

Begin by connecting the included 15VDC power supply to the SGI-44. The power
connection includes a cable clamp feature to prevent accidental power loss.
Loosen the clamp screw, loop the power cable through and re-tighten so it looks
like the photo below. Once connected the POWER LED will illuminate.

Next, make the balanced connection between the JX44 and the SGI-44 using
good quality XLR mic cables. The TX (transmit) output from the JX44 connects to
the RX (receive) input on the SGI-44 (Fig.36). Connect your effect pedals to the
SGI-44’s ¼” hi-Z guitar jacks (Fig.37). Finally , connect the TX output from the SGI­44 to the RX input on the JX44 to complete the loop.

Fig.36 - Balanced XLR connections between

the JX44 and SGI-44.

Once the loop is connected depress the ON switch located
in the SGI section of the rear panel. The SGI LOOP LED
in the SYSTEM MONITOR illuminates when the interface
is active. Both the on-board SGI and the SGI-44 are
transformer isolated to eliminate noise caused by ground
loops. If you hear hum or buzz after connecting try toggling the LIFT switches on
the SGI-44 and on the rear panel of the JX44 at the SGI section. If you don’t hear
your pedals double check your connections.

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Radial Engineering Ltd.

Fig.37 - Hi-Z guitar, effect and tuner connections.

JX44 Owner’s Manual

True to the Music

EXAMPLE 1: WIRELESS GUITAR AND LONG HAUL PEDALBOARD

In this application the JX44 is located near the player’s wireless receivers and
guitar amplifi ers. The SGI-44 and JR5 reside on the player’s pedalboard. The
signal starts at the guitar through the wireless link to the receiver. From the
receiver it fl ows into the JX44 inputs. At this point the SGI LOOP circuit sends the
signal out to the pedals and back again via the SGI interface. The artist can enjoy
the freedom of the wireless guitar and have their pedals out front at their feet along
with the JR5 to control amps.

Up to

300
feet

SGI-44 FEATURES AND FUNCTIONS

C DBA

E

A. RECEIVE - Female XLR receives a

proprietary balanced signal from the
JX44’s SGI-TX output.

B. LIFT - Disconnects the pin-1 ground at

the RECEIVE XLR to reduce noise from
ground loops.

EXAMPLE 2: REMOTE AMPS IN THE STUDIO

Playing guitar in the control room while recording your amps out in the studio can
be particularly advantageous. It allows you to hear the guitar sound exactly as it
will be recorded over the studio monitors. To accomplish this, connect your guitar
to the SGI-44 ¼” guitar input and make a single balanced connection from the SGI­44 to the to the RX jack on the back of the JX44 using an XLR mic cable. In the
control room the SGI-44 lets you connect effect pedals and tuners. In the studio
the JX44 receives the SGI signal and drives the amplifi ers.

Connecting is easy because the SGI interface uses balanced XLR connections
that are 100% compatible with studio patchbays and tie lines. You can take this
setup one step further and add the JR5 footswitch for selecting the amps remotely
from the producers chair.

Up to

300 feet

EXAMPLE 3: LONG HAUL PASSIVE GUITAR CONNECTION

The SGI-44 is ideal for the purists who prefer a real cable over a wireless system
to make a long distance connection between the guitar and the JX44. The Radial
class-A driver and DRAG control combine forces allowing you to dial in the tone
that sounds the most natural despite the long cable run. Add the JR5 footswitch
and you can control your setup remotely from the base of your vocal mic stand.

C. TRANSMIT - Male XLR transmits a

proprietary balanced signal to the JX44’s
SGI-RX input.

D. CABLE CLAMP - Prevents accidental

power disconnect.

E. POWER - Connection for the included

15VDC power supply.

F

IHG

J

F. TUNER OUTPUT - Separately buffered

1/4” high impedance output for electronic
tuner.

G. DRAG™ - Load correction function for

passive pickups.

Up to

300
feet

H. POWER LED - Indicates the power

supply is connected.

I. INPUT - 1/4” jack receives signal from the

output of your effects or guitar.

J. OUTPUT - 1/4” jack sends signal to the

input of your effect pedals or amp.

Radial Engineering Ltd. JX44 Owner’s Manual

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