Re:formant — Discrete Core Analog VCO

Overview

Overview Re:formant is a fully discrete, heavyweight analog saw-core VCO engineered for extreme thermal stability and raw acoustic authority.

At its heart is a heated vintage TCA871 transistor array governed by an active onboard temperature controller, keeping the exponential converter thermally locked regardless of ambient drift. A high-speed dual-comparator core delivers laser-sharp saw resets, driving an actively compensated bleeding triangle, a matched-transistor differential sine shaper, a wide-range PWM pulse generator, and an integrated CMOS sub-octave divider.

Classic through-hole transistor architecture, refined with precision LM336 voltage references and modern circuit design.

Features

Discrete Sawtooth Core

High-speed integrator built with a temperature-compensated matched transistor pair. Delivers fast resets and clean 1V/Oct tracking over more than 5 octaves.

Compensated Triangle

Warm, fundamental-heavy triangle wave shaped with a deliberate inverted reset transient. This subtle harmonic artifact adds natural acoustic bite and presence at the top of the spectrum, giving the low end exceptional clarity and punch in any mix.

Transistor Sine Shaper

Dedicated differential BJT stage shaped for low distortion and smooth acoustic fundamental tone.

Dual Sync Modes

Hard Sync forces an immediate core reset for aggressive harmonic overtone sweeps. Soft Sync gently locks phase to the external source for subtle timbral variations.

CMOS Sub-Oscillator

Dedicated square wave sub-octave output with a front-panel toggle between -1 and -2 octaves below root pitch.

Linear and Exponential FM

Simultaneous exponential and linear frequency modulation inputs, each equipped with dedicated attenuator controls.

Technical Specifications

• Format: Eurorack 3U / 12HP
• Module Depth: 56 mm
• Power Draw: +12V: 38 mA | -12V: 32 mA | +5V: 0 mA
• Outputs: 10.0 Vpp nominal (1k output impedance)
• Waveforms: Sawtooth, Triangle, Sine, Pulse with PWM, Sub-Oscillator
• Pitch Range: 10 Hz – 12 kHz (Audio band) / sub-audio LFO capable
• Tracking: 1V/Octave factory-calibrated across 5+ octaves (+/-2 cents)
• Origin: Hand-assembled, calibrated, and 24h burn-in tested in Białystok, Poland.