SGI-44™ Using & Applications

The following page describes how you can use the Radial SGI-44. This quick look is designed for professional users that are familiar with interfacing guitars and amps with balanced and unbalanced systems. For complete details, we suggest you download the full manual by clicking on the icon at left.


The Radial SGI-44 is a proprietary interface that converts a unbalanced high-impedance guitar signal to a balanced low impedance signal. A second JX44 is used at the receive end to reconvert the signal back to its original form. A combination of class-A buffers and transformer isolation transformers do the work.

Inside each SGI-44 is a second identical signal path that is used to create a return path. This enables the SGI-44 to either be used as a guitar cable extender or as a means to route a distant pedalboard and effects from a wireless receiver back to the guitar amp.

High impedance guitar signals are particularly prone to electro-magnetically induced noise when the coaxial guitar cable exceeds 7 meters (20'). On stage, magnetic fields are everywhere! The sources include guitar and bass amp transformers, high current cables that feed loudspeakers and monitors, electric extension cords, lighting dimmers, and various power supplies.

Using the SGI-44 to extend a guitar cable

As with all audio equipment, make sure signal levels are turned down before making connections. This will eliminate turn on transients from causing harm to more sensitive electronic devices. The Radial SGI-44 is and advanced interface that is plug & play easy to use.

Connect the source to the input, the XLR send to a second SGI-44's receive and the output to a guitar amp. Set the Drag Control to 12 o'clock and listen. Turning the control counter-clockwise will increase the load which will have the effect of darkening the signal. Turning Drag clockwise will brighten the tone. Adjust to suit.

This set-up is often used in the studio or on a stage where the amplifiers are moved off stage to reduce the sound pressure on stage and bleed from the stage going into the audience.

Using the SGI-44 as an effects loop

Connect the SGI-44 as described above only this time, the source will typically come from a wireless system or the Radial JX44. The SGI-44 lets you send the signal to a series of distant guitar pedals that are located at the front of the stage and then using a second unit, it sends the signal back to the amps.

A convenient tuner output lets you monitor the signal at either end. When used with the JX44 and the JR5 footswitch, you can remotely mute the signal for tuning and then bring the system back to life with a single foot stomp.