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Compressor

Reduce the distance between quiet and loud moments.

Visual walkthrough6 configuration controlsSynced audio walkthrough
See how it works ↓

This reduces peaks relative to softer sound. Makeup gain raises the result afterward; it does not change the threshold. Detection is linked for stereo.

01 / Understand

The idea, before the settings.

Above the threshold, the ratio determines how much extra level comes through. At a 4:1 ratio, 4 dB above the threshold becomes 1 dB above it in the steady-state hard-knee example. Attack and release control how fast reduction moves.

Voice / instrumentCompressorLimiter → Output

Use it in AudioRouter

  1. Play both quiet and loud phrases. Begin with Threshold −18 dBFS, Ratio 3:1, Attack 10 ms and Release 150 ms.
  2. Lower Threshold until loud phrases show useful reduction; keep quiet phrases natural.
  3. Adjust Attack to preserve or tame beginnings and Release so recovery does not pump between syllables.
  4. Add Makeup only enough to match the bypassed listening level.

What success looks like

Loud passages move closer to quiet ones. Ratio changes the level above threshold, while Makeup lifts the whole result.

If it does not work

If it only sounds louder, return Makeup to 0 dB and compare again. If reduction is constant, raise Threshold or lower the input.

Select the node to open Properties. Click its name to rename it. While playing, supported parameter-only edits save after a short pause. For structural edits, use Save when the canvas marks a change. Enabled and Bypass are distinct live controls; see the in-app help for their behavior.

02 / Explore

Make the behavior visible.

A pulsing tone arrives in four level sections. Compare the loud third section with the quieter first, then change Threshold and Ratio; this is a simplified envelope compressor.

The example repeats until you press Stop, and control changes are heard immediately. The traces are drawn from that audio, and the line marks the moment you hear. This is not a DSP measurement or control for your running AudioRouter session.

03 / Configure

Every control, with a reason.

01

Threshold

thresholdDb

Level above which compression reduces extra level.

Range / choices-60 dBFS → 0 dBFSDefault-18 dBFS

↓ Lower / alternativeLower values compress more of the signal.

↑ Higher / alternativeHigher values compress fewer moments.

Try thisThreshold −18 dBFS and ratio 3:1 are starting points.

Keep in mind Compression works above the threshold.

02

Ratio

ratio

Strength of level reduction beyond the threshold.

Range / choices1 → 20Default3

↓ Lower / alternativeApproaches unchanged dynamics at 1:1.

↑ Higher / alternativeApplies stronger level reduction.

Try thisAt Compressor 4:1, a steady 4 dB excess becomes 1 dB.

Keep in mind Gate uses reduction below its threshold; Compressor uses reduction above it.

03

Attack

attackMs

How quickly the processor moves into its engaged state.

Range / choices0.1 ms → 200 msDefault10 ms

↓ Lower / alternativeMakes engagement faster.

↑ Higher / alternativeMakes engagement slower.

Try thisCompressor 10 ms is a starting point, not automatic calibration.

Keep in mind For Gate this is opening; for Compressor and Duck this is increasing attenuation.

04

Release

releaseMs

How quickly the processor returns after the triggering condition ends.

Range / choices10 ms → 2000 msDefault150 ms

↓ Lower / alternativeMakes recovery faster.

↑ Higher / alternativeMakes recovery slower.

Try thisTry 200 ms if 100 ms sounds abrupt.

Keep in mind Extremely quick changes can sound like pumping or distortion.

05

Knee

kneeDb

Width of the soft transition around the compressor threshold.

Range / choices0 dB → 24 dBDefault6 dB

↓ Lower / alternativeApproaches an abrupt hard knee at 0 dB.

↑ Higher / alternativeMakes compression begin more gradually around the boundary.

Try thisCompare 0 dB with 6 dB while watching the response curve.

Keep in mind Knee changes the transition, not the ratio far above threshold.

06

Makeup gain

makeupDb

Level added after compression.

Range / choices0 dB → 24 dBDefault0 dB

↓ Lower / alternativeReduces the added gain toward 0 dB.

↑ Higher / alternativeMakes the compressed output louder.

Try thisStart at 0 and increase only enough for a fair bypass comparison.

Keep in mind Added level consumes downstream headroom.

04 / Put it to work

Start with a useful example.

Example 1

Even out speech

  1. Start with threshold −18 dBFS, ratio 3:1, attack 10 ms and release 150 ms.
  2. Speak normally and watch gain reduction on louder phrases.
  3. Add only enough makeup gain for a fair bypass comparison.
Example 2

Keep transients lively

  1. Try increasing attack from 10 to 25 ms.
  2. Listen to the beginning of consonants or percussion.
  3. Place a Limiter later if a sample-peak ceiling is required.

These are starting points. Compare at a comfortable monitoring level and adjust for your own source.

05 / Get unstuck

Small details that matter.

  • A Compressor is not a guaranteed peak ceiling.
  • Excess makeup can clip the next stage.
  • Very fast release can make level changes audible.