Click image to enlarge

X-Amp Menu:
Overview | Development
History of Re-amping
Features & Functions
Specifications | FAQ's
Resources / Manuals
Previous Page

X-Amp re-amping track into two amps

• Active re-amping device
• 100% Class-A signal path
• Two outputs to drive two amps
• Input level overload LED indicator
• Isolated output eliminates ground loops
• Variable output level control

Retail: $200.00, Our Price: $179.99
North American Version, 120 VAC
For other versions, see "Power Supplies" here

Radial X-Amp active re-amplifier

Manufactured under license and protected by US Patent No. 6005950

The Radial X-Amp is an active re-amping device that presents the engineer / producer with a new and innovative creative tool that allows a pre-recorded track from a line level device to drive two guitar amplifiers or effect pedals simultaneously. This opens the door to explore new musical sounds and spur on the creative process.

Following the critically acclaimed Radial JD7 Injector, the X-Amp employs a unique Class-A circuit design that has been optimized for use with guitars. Using the X-Amp is easy: One would, for instance, record a dry track using a high quality direct box, then send this track from the recorder to the X-Amp and then to either guitar amps, effect pedals or combinations thereof.

Recording using the X-Amp has many benefits: Once the basic track has been recorded, replacing or adding tracks can be done well after the session player has gone home. This eliminates tiresome repetition and assures a fresh vibrant performance on the final recording. Furthermore, by driving two amps at the same time, new sounds and textures can be created allowing the engineer – producer to make artistic decisions as the recording progresses.

Features include balanced line level input with LED peak indicator and level control, Class-A circuit topology for optimal reach and frequency response, direct and isolated guitar amplifier outputs, 180º polarity reverse to bring both amps into phase, and dual ground lift options for noise-free operation.

As with all Radial products, the X-Amp is built like a tank to provide years of trouble-free performance. A welded I-beam internal skeleton provides a separate housing for maximum protection against external forces, which may cause stress on the PC board assembly while the outside bookend cover provides a protective zone for the switches, potentiometer and connectors. A full bottom no-slip pad performs double duty by keeping the X-Amp from sliding around when placed on a vibrating amplifier while also providing electrical and mechanical isolation.

Development and Evolution

Les Paul, shown here with Radial's Peter Janis at the 2004 NAMM show, used re-amping in his recordings in the '50's.

Roger Nichol's used his own scratch-built 're-amper' on all the Steely Dan recordings he engineered including 'Aja'.

Radial's JD7 Signal Distribution amp with active re-amping via rear mounted XLR connectors.

X-Amp Menu:
Overview | Development
History of Re-amping
Features & Functions
Specifications | FAQ's
Resources / Manuals
Previous Page

Designed as a creative tool, the Radial X-Amp is an active re-amplifying device that allows prerecorded instrument tracks to be sent through guitar amplifiers and effect devices.

With the X-Amp, you could for instance take a pre-recorded guitar track, and send it through a second distortion pedal and amplifier and then slightly delay the track to add a thick doubling effect. You could also use the X-Amp from a voice track to a distortion pedal to ad some grit to a performance. Another popular use would be to go back and fix a track should an error or glitch somehow appear.

Although the Radial X-amp is new, the process of re-amping tracks has been around for years. Historians credit jazz guitar great Les Paul as the first to employ the concepts of re-amplifying sound in the 1950s as there was no other way to double tracks or create echo effects. In the 1960s, Phil Spector’s work with his famous ‘wall of sound’ employed re-amping techniques. In the 1970s, Roger Nichols built his own ‘re-amper’. Roger used it on all of the Steely Dan records virtually burning out tubes in effort to get the right sound. Only today with the proliferation of affordable high quality multi-track recording has the demand for high-quality recording tools allowed manufacturers to develop devices such the Radial X-amp into commercially viable products.

This is not to say that other re-amping devices have not been available. In 1980, Jensen® Transformers introduced the 1st transformer that could effectuate the process and included an application note on the spec sheet discussing the conversion of balanced to unbalanced guitar signals. The Radial JDI Mk3 in fact employs a newer version of this same transformer and can be easily used as a re-amping device. (See the Radial JDI Owner’s manual for more details).

The forefather to the Radial JD7 Injector (custom built by Radial Chief Engineer Denis Rozon circa 1990) was designed to drive a signal to several guitar amplifiers at once and the introduction of the 1st generation Radial JD7 in 2001 added facilities such as balanced output and input to simplify the re-amping process. The Radial X-Amp is in fact a derivative of the Radial JD7 Injector. It employs the same active balanced input and new Class-A circuit topology as the popular JD7, but in a more affordable and simplified two output configuration.

More detailed information can be found here:
The History of Re-amping

The Challenges in building a better re-amping device

Up until the X-Amp, pretty much all re-amping devices have been passive, transformer-based. These generally work well but do have limitations: Because the same transformer is used to both convert the balanced line level to an unbalanced signal while changing the impedance, one is required to employ workable compromise to get an acceptable tone. Because varying the output level is required to properly match the amplifier’s input level, a potentiometer is required. Since a potentiometer is in fact a variable resistor, changing the level will introduce a load variation, which will inevitably impact the tone. This is not to say that the tone will be bad, it just means that finding the ‘sweet spot’ may be compromised.

The Radial X-Amp was designed in such a way as to solve these problems. To begin, the X-Amp is active. This means that it is equipped with an external power supply to provide the DC to the circuit. The circuit itself is Class-A meaning that it employs a high performance, audiophile buffering circuit to ensure the cleanest and most natural tone. This design allows us to ad several important features and controls that are not possible with simple passive devices. For instance, we introduced a peak-overload detector that lets you monitor the level coming from the recorder and ensure the signal will not overload the circuit. Because we are active, the X-Amp’s output control can be adjusted at will without affecting the tonal character. Furthermore, by adding a second buffer to the signal, we can introduce a second output that to drive a stereo amp set-up or maybe two completely different amps and effects chains at one time. This opens the doors to significantly greater tonal possibilities!

North American Version, 120 VAC
For other versions, see "Power Supplies" here