SOURCE AUDIO ZIO, Analog Front End + Boost

The ZIO is an all-analog preamp and boost pedal from Source Audio, designed in collaboration with Christopher Venter of Shoe Pedals. It was the company’s first all-analog pedal, in a line best known for digital effects. Source Audio’s stated aim is to “make everything sound better”, and it works best as a tone-sweetening pedal rather than a drive pedal. It uses Burr-Brown op-amps chosen for dynamic range, frequency response and feel. **Controls** Circuit: A four-position selector for the preamp type: JFET: A transparent boost with no harshness. Low-Cut: Tightens the low end only, adding headroom and clearing up the mix without changing the low mids. Studio: Inspired by the “Pultec trick” of the 1950s. It trims the midrange and gives clarity. E-Plex: Modeled on the preamp of a ’70s tape echo. It gives a slightly dirty, mid-focused boost with analog warmth. Output: Unity gain is at about 3 to 4. I captured two settings per circuit, one around unity and one with the knob turned all the way up while powering the pedal with 9V. Tone switch (Bright / Medium / Dark): Restores or adjusts some cable coloration, so you can brighten a dull tone or tame shrill highs. In my re-amping setup the effect of this switch was, if all, extremely subtle. So I just set it to MED for all captures. Bypass/Mute switch: Sets the footswitch to act as a true-bypass switch or a mute switch. I recommend watching AndyDemo's demo on YouTube (see below).