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Official effect

Tape Preamp

Low-gain tape-style saturation with added weight in the lows and a deliberately softened top end.

This patch uses the same internal stereo phrase and general overdrive chassis, but backs the saturation amount down, leans harder on the low-shelf stage, and applies a more muted post-drive high shelf. That combination makes it behave more like a preamp thickener than a distortion block: gentle tanh compression, extra body from `contour`, and limited high-frequency edge unless `tone` opens it back up.

  • Drive, Boost & Saturation
  • Library #4
  • 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 patch uses the same internal stereo phrase and general overdrive chassis, but backs the saturation amount down, leans harder on the low-shelf stage, and applies a more muted post-drive high shelf. That combination makes it behave more like a preamp thickener than a distortion block: gentle tanh compression, extra body from `contour`, and limited high-frequency edge unless `tone` opens it back up.

  • Drive, Boost & Saturation
  • 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 short right-channel delay and slight channel-to-channel shelf-EQ offsets before the preamp stage.

  1. 1internal picked-string demo phrase
  2. 2stereo spread with a short right-channel delay
  3. 3high-pass cleanup
  4. 4heavier low-shelf thickening and mild 930 Hz peak shaping
  5. 5gentle single tanh saturation stage
  6. 6restrained post-drive high-shelf compensation
  7. 7dry / wet mix
  8. 8DC blocker
  9. 9output gain trim
  10. 10final tanh limiter

Preview source

An internally generated picked-string phrase is widened to stereo with a short right-channel delay and slight channel-to-channel shelf-EQ offsets before the preamp stage.

Effect core

Gentle single-stage tanh saturation with strong low-shelf thickening and restrained post-drive high-shelf recovery.

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
  • high-pass cleanup
  • heavier low-shelf thickening and mild 930 Hz peak shaping
  • gentle single tanh saturation stage
  • restrained post-drive high-shelf compensation
  • 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 clean stereo preview source with the low-gain preamp path.
  • output_gain_db: Applies final output trim after the preamp path and DC blocker.
  • drive: Raises the input multiplier feeding the single tanh stage, but over a gentler range than the heavier drive patches.
  • tone: Controls the restrained post-drive high shelf after saturation.
  • contour: Pushes the low shelf and broad mid contour ahead of the saturation stage.

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
  • driveTone
  • phraseMono
  • previewShiftSamples

Controls

Audible controls in this DSP

  • mix

    Active

    Blends the clean stereo preview source with the low-gain preamp path.

    Lower settings keep more unprocessed attack; higher settings emphasize the preamp thickness.

  • output_gain_db

    Active

    Applies final output trim after the preamp path and DC blocker.

    Balances loudness without changing the amount of saturation.

  • drive

    Active

    Raises the input multiplier feeding the single tanh stage, but over a gentler range than the heavier drive patches.

    Adds subtle compression and harmonic density instead of moving quickly into overt distortion.

  • tone

    Active

    Controls the restrained post-drive high shelf after saturation.

    Lets the preamp stay dark and tape-like or open up slightly for more presence.

  • contour

    Active

    Pushes the low shelf and broad mid contour ahead of the saturation stage.

    Adds weight and body, making the patch feel fuller rather than sharper.

Analysis

Code-derived notes

Reviewed against the current DSP. This variant stays on the same core topology as the neighboring drive patches, but with substantially lower saturation gain and a darker post-drive shelf so it reads as a thickener instead of a distortion block.

Active blocks

  • demo
  • fx
  • outputStage
  • leftDemo
  • rightDemo
  • driveTone
  • 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/drive-boost-saturation/tape-preamp.dsp
  • Output stage: DC blocker -> output gain trim -> final tanh limiter
  • Library position: 4

More In Drive, Boost & Saturation

Continue through the library

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

Transparent Overdrive

Keeps the dry attack intact while adding a broad low-mid lift and light tanh saturation for edge-of-breakup push.

View How It Works

Amp-Like Overdrive

Mid-forward soft clipping tuned to feel more like a pushed amp stage than a flat clean boost.

View How It Works

Hard-Clip Distortion

Cascaded clipping with reinforced lows and upper mids for tighter attack and more modern bite.

View How It Works