The word "ZIO" is an acronym for Impedance (“Z” is the electrical symbol for impedance), Input (“I”), and Output (“O”). The pedal is designed to take a guitar’s high impedance signal, sweeten the tone with any of its four preamp circuits, and output a strong, low impedance signal that won’t be altered by the buffered dry tones of effect pedals further down the signal chain. High-fidelity, noise-free Burr-Brown op-amps help give ZIO extreme clarity and responsive pick dynamics while maintaining the ideal body and warmth. ZIO has four distinct preamp circuits.

• JFET offers a completely transparent signal boost with zero colouring or distortion.
• LOW-CUT reduces “tubby” bottom-end for a tighter sound with added headroom.
• STUDIO finds inspiration from the time-honoured “Pultec Trick,” a studio technique that adds clarity by cutting the “mud frequencies” and adding mid-range articulation. E-
• PLEX captures the focused and subtle grit of the preamps found in vintage Echoplex Tape Delay units. The ZIO’s TONE toggle offers three different levels of capacitance (or simulated cable length) to brighten or darken the tone.

ZIO offers four discrete preamp circuits: JFET, LOW-CUT, STUDIO, and E-PLEX.  Each circuit has its own unique character and has been carefully crafted to maximise feel and performance.  JFET, LOW-CUT, and STUDIO are all chiefly low-distortion circuits, while E-PLEX will add a bit of grit to your signal at most output levels.  Each preamp circuit comprises the highest-quality components and features an all-original design. 

After bench-testing some classic op-amps used in overdrive, distortion, and boost stompboxes such as the ubiquitous TL072 and about half a dozen popular op-amp chips spanning back to the 1970s, we selected the Burr-Brown for its pure tonality, dynamic range, frequency response, and overall feel. 

While other chips had certain properties such as sounding "too bright", "too thin", "too distorted", etc., the unmatched transparency and headroom of this 14-legged Burr Brown OPA chip was the perfect match for the ZIO's mission of delivering you your own tone, but better. 

After bench-testing some classic op-amps used in overdrive, distortion, and boost stompboxes such as the ubiquitous TL072 and about half a dozen popular op-amp chips spanning back to the 1970s, we selected the Burr-Brown for its pure tonality, dynamic range, frequency response, and overall feel. 

While other chips had certain properties such as sounding "too bright", "too thin", "too distorted", etc., the unmatched transparency and headroom of this 14-legged Burr Brown OPA chip was the perfect match for the ZIO's mission of delivering you your own tone, but better.