WMD C4RBN Advanced 4 Pole MMF

WMD C4RBN – Multi-Mode SVF Filter with Saturation & Wavefolder

The C4RBN (pronounced Carbon) by WMD is a flexible state-variable filter with 2-pole and 4-pole modes, capable of everything from smooth analog filtering to aggressive, harmonically rich tones. Building on WMD’s legacy of SVF design, C4RBN adds switchable saturation, a wavefolder, and deep CV control, making it a powerful tool for shaping sound in both subtle and extreme ways.

The module features two serial 2-pole filter cores, with individual outputs for low-pass, band-pass, and high-pass from the first core, plus a switchable 4-pole output with selectable filter type. Use it as a clean SVF, a saturated character filter, or a feedback-driven wave-mangler — the flexibility is enormous.

The input stage offers four selectable saturation intensities, and can be swapped for the output wavefolder from WMD’s Synchrodyne. Both are accessible via a push-button interface and are CV-controllable for dynamic tone shaping.

Additional features include:

• 1V/Oct input for tracking the filter like an oscillator

• FM input with inverting attenuator for negative or positive frequency modulation

• Ping input for triggering vactrol-like responses

• CV control over resonance, FM, saturation, and cutoff

Self-oscillation kicks in around 3 o’clock on the resonance control, allowing for filter pinging, tonal percussion, or sine wave generation.

Whether you're after clean sweeps, rubbery basslines, or snarling distortion-drenched resonance, C4RBN gives you a compact, playable filter with extensive performance and modulation options.

Key Features

• State-variable filter with 2-pole and 4-pole modes

• 2-pole LP/BP/HP outputs and switchable 4-pole output

• Input stage with 4 levels of analog saturation (CV controllable)

• Switchable wavefolder (from WMD Synchrodyne)

• Inverting attenuator for FM input

• CV inputs for resonance, cutoff, saturation, and FM

• Ping input for fast, snappy filter pings

• Resonance up to self-oscillation

• Temperature-compensated 1V/Oct input for pitch tracking

• Excellent for subtle tone shaping or aggressive filtering

Available in-store for demo.