JX2 Switchbone Amp Switcher from Tonebone
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(Click for a close-up) |
February 7, 2003
Radial Engineering manufacturer of Tonebone brand of products, introduced the Radial JX2 Switchbone, a two channel guitar amplifier AB-Y selector that allows two amps to be used in tandem without introducing hum or buzz and does so without affecting the original tone or gain of the guitar.
According to Radial President, Peter Janis: "When we introduced the Radial JD7 Injector, we received many calls from guitarists wanting a similar device for use on stage that could allow them to use more than one amp at the same time. The first problem in running to amps simultaneously stems from different grounding schemes used by amplifier manufacturers and the various reference voltages that, when connected together, cause ground loops and buzz making them unusable. We solved this problem by introducing high-quality isolation transformers into the circuit, thus eliminating the hum and buzz problem altogether."
"But it does not end there. As soon as a guitar pick-up 'sees' more than one amplifier, the output level will drop to where it sounds thin and has no punch. We solve this problem by introducing a proprietary Class-A pre-amplifier stage that has been optimized for guitar signals. Class-A circuits are greatly preferred by audiophiles over typical op-amps due to their sonic performance. The JX2's Class-A circuit does not suffer the ill-effects from zero-cross distortion, has significantly less harmonic distortion, very low inter-modulation distortion and almost zero phase distortion. This produces a very linear response that translates well for the guitar and retains the character without adding color or spectral shift. As you can imagine, changing the tone of a vintage '57 Strat would not sit well with a serious player!"
Janis continues: "But this is still not sufficient. We found that when the guitar no longer 'sees' the amplifier, the sound becomes too crystalline or too perfect. This is because the natural relationship between the guitar pick-up and the amplifier is lost. This problem is solved with our exclusive Drag Control. Drag essentially is a loading and impedance correction circuit that re-introduces the natural relationship between the guitar and amp, while simulating the loss from the resistance and capacitance in the cable. With a single knob, you can quickly dial-in the perfect tone. It is both fun and very musical."
The Radial JX2 Switchbone features a guitar input, two amplifier outputs, a tuner out, three footswitches and LED indicators. The center 'toggle' footswitch allows the user to transition from one amp to the other by simply depressing it. The second 'both' foot switch on the left hand side allows the guitarist to select between either amp 1 or 2 or both. An LED indicator arrangement provide instant status on which outputs are on and which ones will go to 'standby' by way of either flashing, constant-on, or simply off. This innovative set-up eliminates 'tap dancing' when transitioning between amplifier set-ups. A ground lift switch ads yet another level of noise elimination while a polarity switch flips the relative phase by 180 to optimize the amplifier set-up.
Finally, a booster switch on the right hand side activates a Class-A power booster circuit with a variable level control, providing a clean, linear increase on both channels. This is particularly useful when working with overdriven amplifiers that require an extra bit of kick or for jazz guitar where retaining the natural tone of the instrument is critical. The power booster control panel is outfitted with two switches labeled 'switch select' and 'mid boost'. The 'switch select' may be set for gain, mid-boost only (for added cut for soloing without adding gain) or may be set to mute mode should one simply want to turn off the outputs while tuning. The separate tuner output keeps the tuner out of the audio circuit thus eliminating its circuit effect on the guitar. The mid control switch may be set to off, +5dB and +10dB mid range boost.
The Radial JX2 Switchbone comes equipped with a 15VDC supply to provide ample voltage and assure the cleanest possible sound for the audio circuit. The JX2 Switchbone retails at USD$300. For more information, visit their web site at www.radialeng.com. | 
