Source Audio ZIO Analog Front End + Boost

Source Audio’s ZIO Analog Front End + Boost pedal was born from a beautifully simple mission: make everything sound better through pure analog circuitry. Developed in collaboration with Christopher Venter from SHOE Pedals, this all-analog preamp and boost unit offers four distinct preamp circuits, each capable of providing up to +20dB of additional output boost. The ZIO serves multiple roles throughout your signal chain – from shaping your initial tone at the front of your effects chain to acting as a clean volume boost after drive pedals, or functioning as a restorative device at the end of your pedalboard to recreate that direct guitar-to-amp connection sound.

The name ZIO represents Impedance, Input, and Output – perfectly describing its core function of converting your guitar’s high impedance signal into a strong, low impedance output that won’t be compromised by buffered effects downstream. Four carefully crafted preamp circuits provide distinct tonal options: JFET offers completely transparent signal boost with zero colouration, LOW-CUT tightens the bottom end for added headroom, STUDIO employs the classic “Pultec Trick” to cut mud frequencies while adding mid-range clarity, and E-PLEX captures the focused character and subtle grit of vintage Echoplex preamps. High-fidelity Burr-Brown op amps maintain exceptional clarity and responsive pick dynamics while preserving natural body and warmth.

The ZIO’s TONE toggle provides three capacitance levels that simulate different cable lengths, allowing you to brighten or darken your tone as needed. The BRIGHT position introduces minimal capacitive load for maximum treble content, MED replicates approximately 15 feet of cable, while DARK simulates longer cable runs to tame excessive brightness. After extensive testing of classic op-amps used in various stompboxes, Source Audio selected the 14-pin Burr Brown OPA chip for its unmatched transparency, dynamic range, and frequency response – rejecting alternatives that proved too bright, thin, or distorted for the ZIO’s mission of pure tonal enhancement.