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Official effect

Dual-Engine Serial/Parallel Reverb

Currently the same asymmetric left-delay/right-diffuser split as Dual-Mono Split FX rather than a serial/parallel dual reverb engine.

The current split or dual-engine family does not run a configurable serial/parallel routing graph. Instead, it treats the two channels differently: the left side gets a low-shelf boost into a short delay, while the right side gets a high-shelf tilt into a short diffuser. `mix` crossfades each wet branch against its dry channel, `width` raises the left low-shelf boost and the right diffuser feedback, `motion` sets both the short delay time and the diffuser delay, and `tone` shapes the right-side high shelf. The result then passes through the shared DC-blocking, output-gain, and soft-limiting stage.

  • Stereo, Utility & Routing
  • Library #268
  • 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

The current split or dual-engine family does not run a configurable serial/parallel routing graph. Instead, it treats the two channels differently: the left side gets a low-shelf boost into a short delay, while the right side gets a high-shelf tilt into a short diffuser. `mix` crossfades each wet branch against its dry channel, `width` raises the left low-shelf boost and the right diffuser feedback, `motion` sets both the short delay time and the diffuser delay, and `tone` shapes the right-side high shelf. The result then passes through the shared DC-blocking, output-gain, and soft-limiting stage.

  • Stereo, Utility & Routing
  • 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 the shared 19-sample right-channel offset before the left and right channels are processed by different simple utility branches.

  1. 1internal picked-string demo phrase
  2. 2shared stereo spread with a short right-channel delay
  3. 3left low-shelf tilt and short delay branch
  4. 4right high-shelf tilt and short diffuser branch
  5. 5per-channel dry / wet crossfade
  6. 6DC blocker
  7. 7output gain trim
  8. 8final tanh limiter

Preview source

An internally generated picked-string phrase is widened to stereo with the shared 19-sample right-channel offset before the left and right channels are processed by different simple utility branches.

Effect core

Current asymmetric left-delay and right-diffuser split shared with Dual-Mono Split FX.

Signal path

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

  • internal picked-string demo phrase
  • shared stereo spread with a short right-channel delay
  • left low-shelf tilt and short delay branch
  • right high-shelf tilt and short diffuser branch
  • per-channel dry / wet crossfade
  • 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: Crossfades or scales the current wet layer against the dry stereo preview source.
  • output_gain_db: Applies final post-effect level trim after DC blocking and before the output limiter.
  • width: Raises the low-shelf boost on the left branch and the diffuser feedback on the right branch.
  • motion: Sets the short left-side delay time and the right-side diffuser delay length.
  • tone: Sets the high-shelf tilt on the right-side branch.

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
  • leftFx
  • rightFx
  • phraseMono

Controls

Audible controls in this DSP

  • mix

    Active

    Crossfades or scales the current wet layer against the dry stereo preview source.

    Higher settings make the processed layer more dominant relative to the dry phrase.

  • output_gain_db

    Active

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

    Matches loudness without changing the underlying effect structure.

  • width

    Active

    Raises the low-shelf boost on the left branch and the diffuser feedback on the right branch.

    Higher settings thicken the left side and make the right-side smear linger longer.

  • motion

    Active

    Sets the short left-side delay time and the right-side diffuser delay length.

    Higher settings lengthen both branches and make the split more noticeable.

  • tone

    Active

    Sets the high-shelf tilt on the right-side branch.

    Higher settings brighten the diffused right-side layer.

Analysis

Code-derived notes

Current implementation shares the exact same asymmetric dual-branch architecture with Dual-Mono Split FX. It is not a serial/parallel reverb graph yet.

Active blocks

  • demo
  • fx
  • outputStage
  • leftDemo
  • rightDemo
  • leftFx
  • rightFx
  • phraseMono
  • previewShiftSamples
  • leftDual
  • rightDual
  • pickedVoice
  • maxDelaySamples
  • diffuser
  • fund
  • pickEnv
  • ampEnv
  • triggerAt

Inactive helpers

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

Warnings

No current warnings are attached to this effect.

Source

  • library/stereo-utility-routing/dual-engine-serial-parallel-reverb.dsp
  • Output stage: DC blocker -> output gain trim -> final tanh limiter
  • Library position: 268

More In Stereo, Utility & Routing

Continue through the library

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

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Currently the same short per-side delay widener as Stereo Image Shaper rather than a true mid/side matrix.

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Speaker Sim

Applies a speaker-style band-pass contour and top-end trim to simulate a simpler output stage.

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