Noise Engineering Pura Ruina

Three-stage CV-controlled full-wave rectifier for unique harmonic distortion

8 HP Eurorack module

Pura Ruina is a three-stage full-wave rectifier designed for audio-rate distortion. Full-wave rectification flips negative signal portions to positive, creating harmonic content unlike standard wavefolding or clipping. Stage 1 passes the dry signal; stage 2 applies one round of FWR (doubling the fundamental frequency); stage 4 applies FWR to stage 2; stage 8 applies FWR to stage 4. Each stage has its own volume knob, CV input, and individual output, plus all four feed into a Sum output. Knobs act as offsets when CV is patched. Simple waveforms like sines become harmonically rich, and complex signals get shredded into new textures.

Features

• Three cascading full-wave rectification stages
• Individual CV control per stage (0-5V)
• Global All CV input for simultaneous control
• Individual output per stage plus summed output
• Knobs act as offsets when CV is patched
• Creates unique harmonic distortion unlike wavefolding or clipping
• Can function as a complex VCA with harmonic shaping

Controls & Jacks (15)

• 8— Triple full-wave rectification stage volume. Acts as offset for CV 8 input.
• 4— Double full-wave rectification stage volume. Acts as offset for CV 4 input.
• 2— Single full-wave rectification stage volume. Acts as offset for CV 2 input.
• 1— Dry signal volume. Acts as offset for CV 1 input.
• In— Audio input.
• All CV— Simultaneous CV control of all four stage volumes. 0-5V.
• Sum Out— Summed output of all four stages.
• CV 8— CV control for triple rectification stage volume. 0-5V.
• CV 4— CV control for double rectification stage volume. 0-5V.
• CV 2— CV control for single rectification stage volume. 0-5V.
• CV 1— CV control for dry signal volume. 0-5V.
• Out 8— Individual output for triple rectification stage.
• Out 4— Individual output for double rectification stage.
• Out 2— Individual output for single rectification stage.
• Out 1— Individual output for dry signal.

Explore the interactive Pura Ruina panel on BleepDex — tap any control to learn what it does.