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Official effect

Harmonic Exciter

Parallel high-band saturator that adds clipped upper harmonics back on top of the dry signal.

This effect keeps the dry signal intact and adds a second branch that high-passes the audio, drives it through tanh saturation, and scales it back in parallel. `focus` sets the crossover into that exciter branch, `motion` raises the saturation amount, and `rate` controls the exciter branch level rather than any time-based modulation.

  • Filter, Wah & Envelope
  • Library #83
  • 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 effect keeps the dry signal intact and adds a second branch that high-passes the audio, drives it through tanh saturation, and scales it back in parallel. `focus` sets the crossover into that exciter branch, `motion` raises the saturation amount, and `rate` controls the exciter branch level rather than any time-based modulation.

  • Filter, Wah & Envelope
  • 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 high-passed exciter branch
  4. 4soft saturation on the exciter branch
  5. 5sum with the dry signal
  6. 6dry / wet mix
  7. 7DC blocker
  8. 8output gain trim
  9. 9final 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 high-passed saturation branch blended back with the dry signal.

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 high-passed exciter branch
  • soft saturation on the exciter branch
  • sum with the dry signal
  • 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: Sets the high-pass cutoff feeding the exciter branch.
  • motion: Raises the saturation amount applied to the exciter branch.
  • rate: Sets the gain of the exciter branch after saturation.

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

    Sets the high-pass cutoff feeding the exciter branch.

    Moves the added harmonic emphasis higher or lower in the spectrum.

  • motion

    Active

    Raises the saturation amount applied to the exciter branch.

    Adds more harmonic edge and brightness.

  • rate

    Active

    Sets the gain of the exciter branch after saturation.

    Changes how much of the excited high-band content is blended in; it is not a time control in the current code.

Analysis

Code-derived notes

Current implementation is a distinct parallel harmonic-enhancement path rather than a time-modulated filter.

Active blocks

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

Inactive helpers

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

Warnings

No current warnings are attached to this effect.

Source

  • library/filter-wah-envelope/harmonic-exciter.dsp
  • Output stage: DC blocker -> output gain trim -> final tanh limiter
  • Library position: 83

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