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Official effect

Optical Compressor

Smooth envelope-leveling compressor that currently uses the same gain-scaling core as Studio Compressor.

This preview currently shares the same processing path as Studio Compressor: a low-passed absolute-value envelope drives a gain-scaling stage, followed by a low shelf and a post-processing high shelf. It already behaves like a gentle leveler, but there is no separate opto-style attack/release model in the current code.

  • Compression, Gate & EQ
  • Library #42
  • 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 preview currently shares the same processing path as Studio Compressor: a low-passed absolute-value envelope drives a gain-scaling stage, followed by a low shelf and a post-processing high shelf. It already behaves like a gentle leveler, but there is no separate opto-style attack/release model in the current code.

  • Compression, Gate & EQ
  • 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 dynamics or EQ core.

  1. 1internal picked-string demo phrase
  2. 2stereo spread with a short right-channel delay
  3. 3envelope-following gain reduction
  4. 4low-shelf contour shaping
  5. 5post-processing high-shelf tone shaping
  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 dynamics or EQ core.

Effect core

Envelope-dependent gain reduction with post-compression low-shelf contouring and high-shelf tone shaping.

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
  • envelope-following gain reduction
  • low-shelf contour shaping
  • post-processing high-shelf tone shaping
  • 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 processed path after the core effect.
  • output_gain_db: Applies final post-effect level trim after DC blocking and before the output limiter.
  • squeeze: Raises the multiplier applied to the smoothed input envelope in the denominator of the gain-scaling stage.
  • tone: Adjusts the post-processing high shelf.
  • contour: Raises the numerator of the gain-scaling stage and adjusts the post-processing low shelf.

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
  • gateCore
  • phraseMono
  • previewShiftSamples

Controls

Audible controls in this DSP

  • mix

    Active

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

    Lower settings keep more dry attack and natural dynamics; higher settings push the processed behavior forward.

  • output_gain_db

    Active

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

    Matches loudness without changing the actual dynamic or EQ structure.

  • squeeze

    Active

    Raises the multiplier applied to the smoothed input envelope in the denominator of the gain-scaling stage.

    Increases leveling strength and sustain.

  • tone

    Active

    Adjusts the post-processing high shelf.

    Changes how much brightness survives after the leveling stage.

  • contour

    Active

    Raises the numerator of the gain-scaling stage and adjusts the post-processing low shelf.

    Adds more low-end body and changes how full the compressed signal feels.

Analysis

Code-derived notes

Current implementation shares the same envelope-leveling compressor core as Studio Compressor, Sustain Compressor, FET Compressor, Parallel Compressor, Multi-Band Compressor, and Upward Compressor.

Active blocks

  • demo
  • fx
  • outputStage
  • leftDemo
  • rightDemo
  • gateCore
  • 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/compression-gate-eq/optical-compressor.dsp
  • Output stage: DC blocker -> output gain trim -> final tanh limiter
  • Library position: 42

More In Compression, Gate & EQ

Continue through the library

Each effect page uses the same generated description pipeline and compiled waveform preview assets.

Studio Compressor

Balanced envelope-controlled leveling with mild low-end contour shaping and a restrained high-shelf finish.

View How It Works

Parametric EQ

Three-stage EQ with low shelf, one sweepable mid peak, and a final high shelf.

View How It Works

Dynamic EQ

Three-stage static EQ that currently uses the same shelf-plus-peak core as Parametric EQ.

View How It Works