The Radial Engineering Tonebone AC Driver is a studio-quality preamp in a pedal form factor. It's designed to amplify acoustic instruments on the stage, employing a Class-A buffered circuit for pristine audio. To help you achieve the tonal profile you're looking for, a low-cut filter, a notch filter, and a level knob are all supplied, as is a 180° phase switch to bust feedback.

   

The footswitch mutes the pedal so you can tune quietly on stage, provided you feed your signal to a dedicated tuner by means of the dedicated 1/4" tuner output. In addition to the tuner output, a 1/4" instrument output for acoustic amplifiers is on hand, as is an XLR output with a dedicated ground-lift switch for the house PA. Heavy duty components are used throughout to ensure the pedal's durability. The pedal requires a separately-available 9 VDC power supply.

Controls at a Glance

• Notch Knob: Sets the center frequency for the notch filter, which is used to eliminate feedback
• Low Cut Knob: Variable filter that rolls off low frequencies and controls bass resonance
• Level Knob: Controls the output of both the XLR and 1/4" outputs
• Notch Q Switch: 3-position switch bypasses the notch filter or selects between regular or deep notches; this control works in conjunction with the notch-frequency knob
• 180° Phase Reverse Switch: Reduces onstage feedback by reversing the polarity of the XLR output
• Mute Switch and LED: Footswitch turns off all outputs except the tuner output, and can help with silent tuning on stage

I/O

• A 1/4" input accepts your acoustic guitar's signal, and you can route to a 1/4" output and a balanced XLR connection for the house; a 1/4" tuner output transmit dry signal regardless of the footswitch position
• Durability Features
• Switches with metal outer casing are rated at over 20,000 cycles for durability
• Glass-filled nylon XLR connector with large nickel-silver pin contacts are tougher than steel
• A double-sided military spec circuit board has been employed to ensure durability, providing a full ground plane to reduce radio frequency interference
• An I-Beam 14-gauge chassis prevents the circuit board from being torqued