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Official effect

Fixed Filter Bank

Parallel four-band band-pass bank that statically redistributes energy into a few resonant lanes.

This core simply sums four band-pass stages with fixed gains while `focus` and `motion` move some of the band centers. There is no time modulation or envelope interaction in the current implementation, and the shared `rate` control is declared but inactive.

  • Filter, Wah & Envelope
  • Library #78
  • Preview 8s

Waveform preview

Static peaks come from the compiled FAUST preview render. The live scope is drawn from the browser playback output in real time.

Timeline
0:00 / 0:08
Source
Compiled browser preview
Live oscilloscope from the browser playback output.AnalyserNode keeps the signal path unchanged while exposing the waveform.

How It Works

Technical view

This core simply sums four band-pass stages with fixed gains while `focus` and `motion` move some of the band centers. There is no time modulation or envelope interaction in the current implementation, and the shared `rate` control is declared but inactive.

  • Filter, Wah & Envelope
  • band-pass filtering
  • waveshaping / saturation
  • delay processing
  • oscillator / LFO modulation
  • DC blocking

Signal Path

Compiled preview chain

Preview source: An internally generated picked-string phrase is widened to stereo with a 19-sample right-channel delay and slight left/right shelf-EQ offsets before it hits the filter core.

  1. 1internal picked-string demo phrase
  2. 2stereo spread with a short right-channel delay
  3. 3parallel four-band band-pass bank
  4. 4dry / wet mix
  5. 5DC blocker
  6. 6output gain trim
  7. 7final tanh limiter

Preview source

An internally generated picked-string phrase is widened to stereo with a 19-sample right-channel delay and slight left/right shelf-EQ offsets before it hits the filter core.

Effect core

Parallel four-band band-pass bank with static gains and no active time modulation.

Signal path

The static waveform and the live player both reflect this compiled signal chain.

  • internal picked-string demo phrase
  • stereo spread with a short right-channel delay
  • parallel four-band band-pass bank
  • dry / wet mix
  • DC blocker
  • output gain trim
  • final tanh limiter

Controls that matter

These are the currently active controls detected in the FAUST source for this effect.

  • mix: Blends the untouched stereo preview source with the filtered path after the effect core.
  • output_gain_db: Applies final post-effect level trim after DC blocking and before the output limiter.
  • focus: Moves the lower and mid-upper band-pass centers inside the parallel filter bank.
  • motion: Moves the middle and upper band-pass centers inside the parallel filter bank.
  • rate: Declared in the shared control set but unused in the current preview code.

Code-backed analysis

The generated description is tied to the active helper blocks and routing found in the current DSP.

  • demo
  • fx
  • outputStage
  • leftDemo
  • rightDemo
  • filterCore
  • phraseMono
  • previewShiftSamples

Controls

Audible controls in this DSP

  • mix

    Active

    Blends the untouched stereo preview source with the filtered path after the effect core.

    Lower settings preserve more dry attack and full-band tone; higher settings emphasize the filter treatment.

  • output_gain_db

    Active

    Applies final post-effect level trim after DC blocking and before the output limiter.

    Matches loudness without changing the filter behavior itself.

  • focus

    Active

    Moves the lower and mid-upper band-pass centers inside the parallel filter bank.

    Rebalances which fixed bands dominate the result.

  • motion

    Active

    Moves the middle and upper band-pass centers inside the parallel filter bank.

    Shifts the brighter resonant peaks higher or lower.

  • rate

    Active

    Declared in the shared control set but unused in the current preview code.

    Changing it currently has no effect on the sound.

Analysis

Code-derived notes

Current implementation shares the same four-band static filter-bank core across Fixed Filter Bank and Resonator Bank, and the shared rate control is inactive.

Active blocks

  • demo
  • fx
  • outputStage
  • leftDemo
  • rightDemo
  • filterCore
  • phraseMono
  • previewShiftSamples
  • pickedVoice
  • fund
  • pickEnv
  • ampEnv
  • triggerAt
  • maxDelaySamples

Inactive helpers

  • synthVoice
  • organVoice
  • bellVoice
  • softsat
  • quantize
  • combLP
  • echoOnly
  • diffuser

Warnings

No current warnings are attached to this effect.

Source

  • library/filter-wah-envelope/fixed-filter-bank.dsp
  • Output stage: DC blocker -> output gain trim -> final tanh limiter
  • Library position: 78

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