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 the workhorse. It is multi-mode, so one node covers several jobs:

• Filter Type selects LP, HP, BP, or Notch.
• Topology selects Biquad or Zero-Delay. Zero-Delay holds together better at high resonance.
• Cutoff and Resonance are parameters and live control inputs, so either can be modulated.

EQ is the corrective counterpart: eight parametric bands with independent frequency, gain, and Q, edited directly on the node display. Use Filter when the filter is part of the sound and you want to sweep it; use EQ when you want to fix or balance a spectrum and leave it there.

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, available both as a parameter and as a live input.

Time and space

• Delay is a stereo delay with Digital, Tape, and BBD loop characters and optional ping-pong routing. Time runs from 0 to 8000 ms, and it also accepts a Clock Divider phase output for tempo-synced echoes — see Sequencing and Clock.
• Reverb adds space. Decay, Damping, and Mix are also live inputs.
• Granular Delay records into a rolling buffer and sprays overlapping grains back out, for shimmer and frozen texture rather than clean repeats. Hold freezes capture so the current memory keeps replaying. Density either runs free in grains per second or locks to a patched clock.

Movement and width

• Chorus thickens and widens. Its single Audio Out port carries stereo audio.

Drive and degradation

• Saturation adds warmth or grit. Character picks the flavour, Drive sets the amount, and Tone and Tilt shape what comes out. It compensates level automatically, so raising Drive does not simply make the patch louder.
• Bitcrusher degrades the signal with Bits and Downsample for lo-fi character.

Saturation and Bitcrusher both add harmonics, so they are worth trying in either order against a filter — the section on ordering below applies most audibly here.

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.
• Pan places the signal in the stereo field. See Stereo and Panning for width, splitting, and merging.

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 → Saturation → Delay → Reverb.
2. Reverb Audio Out → Audio Output.

graph LR
    OSC[Oscillator] -->|Audio| FILT[Filter]
    FILT -->|Audio| SAT[Saturation]
    SAT -->|Audio| DLY[Delay]
    DLY -->|Audio| REV[Reverb]
    REV -->|Audio| OUT[Audio Output]

Reordering these nodes changes the sound. Saturating after the filter drives a shaped signal; saturating before it lets the filter tame the harmonics that drive adds. Delay before reverb gives distinct repeats that then wash out; reverb before delay smears first and repeats the wash.

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.
• Audio ports carry stereo through one connection rather than a left/right pair. The literal output labels differ: Chorus uses Audio Out, Delay uses Stereo Output, and Pan uses Stereo Audio. Check the port contract before patching.
• Use Filter for filtering you intend to move, and EQ for tone you intend to set.