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Filters and Effects

Filters and Effects

Audio flows through a chain of nodes from the oscillator to the Audio Output. Each step has an audio input on the left and an audio output on the right, so you insert filters and effects by patching them in series. Order matters: a filter before a distortion sounds different from the same two swapped.

Filters

A filter removes or emphasises part of the spectrum. It is the single most musical place to apply modulation.

  • Filter is a multi-mode filter with Cutoff, Resonance, a Filter Type, and a Topology. Its Cutoff and Resonance inputs accept control signals.
  • State Variable Filter exposes Primary, Band Pass, and High Pass outputs at once, so you can tap several responses from one filter.

Modulate Cutoff with an ADSR or LFO for the classic subtractive sweep. See Modulation and Envelopes, and use Map Range to scale the modulation into a useful cutoff span.

Effects

Most effects take Audio In and return processed audio. Many carry a Mix control that blends dry and wet.

  • Reverb adds space. Decay, Damping, and Mix are also live inputs.
  • Chorus thickens and widens. It outputs a stereo pair on Left and Right rather than a single audio port.
  • Flanger sweeps a short delay with a Feedback control for the jet-like effect.
  • Bitcrusher degrades the signal with Bits and Downsample for lo-fi character.

Dynamics

Use dynamics to control level. Remember from Data Types and Conversion that a normalized signal can still clip when summed or amplified.

  • Compressor evens out level with Threshold, Ratio, Attack, Release, and Makeup. Its Sidechain input lets one signal duck another.
  • Limiter sets a hard Ceiling. Place it last to stop the output overshooting.

Mixing and Gain

  • Mix sums up to eight inputs (Input A to Input H) each with its own gain. It does not limit the result, so a loud sum can clip — follow it with a Limiter if needed.
  • Gain and VCA set level. Use the VCA when the level is controlled by another signal, such as an envelope.

Common Patch Examples

Subtractive voice

  1. Oscillator Signal → Filter Audio In.
  2. ADSR Envelope → Map Range → Filter Cutoff.
  3. Filter Audio Out → VCA Signal → Audio Output Audio In.
graph LR OSC[Oscillator] -->|Signal| FILT[Filter] ADSR[ADSR] -->|Envelope| MAP[Map Range] MAP -->|Cutoff| FILT FILT -->|Audio| VCA[VCA] VCA -->|Audio| OUT[Audio Output]

Serial effects chain

  1. Oscillator → Filter → Flanger → Reverb.
  2. Reverb Audio Out → Audio Output.
graph LR OSC[Oscillator] -->|Audio| FILT[Filter] FILT -->|Audio| FLANG[Flanger] FLANG -->|Audio| REV[Reverb] REV -->|Audio| OUT[Audio Output]

Reordering these nodes changes the sound. Try the reverb before and after the flanger.

Parallel layers into a mix

  1. Send two or more sources into Mix inputs A and B.
  2. Set each input gain to balance them.
  3. Mix Output → Limiter → Audio Output to keep the sum in range.
graph LR SRCA[Source A] -->|Input A| MIX[Mix] SRCB[Source B] -->|Input B| MIX MIX -->|Audio| LIM[Limiter] LIM -->|Audio| OUT[Audio Output]

Rules of Thumb

  • Audio chains run left to right. The order of filters and effects changes the result.
  • Cutoff is the most rewarding modulation target. Drive it from an ADSR or LFO.
  • Use a Mix control to blend dry and wet on an effect.
  • Mix sums and can exceed range. Watch levels and place a Limiter last.
  • Chorus and the State Variable Filter have more than one output port. Check which one you are patching.