Purpose

Compress is a compressor and brickwall limiter in one op. Four characters change how it grabs the signal: clean is transparent, glue sums a bus together, opto is slow and smooth, punch emphasizes the hit. The sidechain port takes audio or a control stream, so anything can duck anything: a kick bus, an audio reactor band, a physical contact event. It works on mono, stereo, or a full multi-channel speaker bus.

Use

Insert it inline on a voice, a bus, or the master. Wire audio into in and out onward. Pull Threshold down until the loud parts start to move, set Ratio for how hard they are held, and use Makeup (or Automakeup) to bring the level back. For ducking, wire the trigger source into sidechain and turn Usesidechain on. Switch Mode to limit for a ceiling instead of a ratio.

Inputs and outputs

• Input 0: in is the signal to compress. Mono, stereo, or multi-channel. Required.
• Input 1: sidechain is an optional detector source, audio or control.
• Output 0: out emits the compressed signal in the same shape as the input.

Controls

• Mode: compress for ratio compression, limit for a brickwall limiter.
• Character: clean, glue, opto, or punch.
• Threshold: level in dB where gain reduction starts.
• Ratio: how strongly signal above the threshold is reduced, 1:1 to 20:1.
• Knee: width of the soft transition around the threshold in dB.
• Attack and Release: how fast reduction engages and lets go, in milliseconds.
• Autorelease: program-dependent release instead of the fixed Release time.
• Makeup and Automakeup: output gain to compensate the reduction, manual or automatic.
• Mix: dry/wet blend for parallel compression.
• Detect: detector law. peak, rms, or hybrid. Rmsms sets the RMS window.
• Link: channel linking. linked, unlinked, or pairs.
• Usesidechain: detect from the sidechain input instead of in.
• Schpf: high-pass on the sidechain detector so bass does not pump the compressor.
• Listen: monitor the sidechain detector signal.
• Lookahead: detector lookahead up to 10 ms, useful in limit mode for catching peaks.

Notes

• Sidechain ducking works from control streams too, so an event or an envelope can duck a bus without any audio routing tricks.
• glue with a slow Attack and Autorelease is the bus-compressor setting; punch with a fast Release exaggerates transients.
• Keep Mix below full for parallel compression: crushed copy blended under the dry signal.

Ports

Inputs

• in row required
  audio_pcm_f32_mono_v1audio_pcm_f32_stereo_v1audio_pcm_f32_multi_v1
• sidechain row
  audio_pcm_f32_mono_v1audio_pcm_f32_stereo_v1audio_pcm_f32_multi_v1control_f32_v1

Outputs

• out row
  mirror_input

Parameters

Mode (Mode) Menu op('compress').par.Mode

Default:

compress

Options:

compress, limit

Character (Character) Menu op('compress').par.Character

Default:

clean

Options:

clean, glue, opto, punch

Threshold (Threshold) Float op('compress').par.Threshold

Default:

-18

Range:

-60 to 0

Ratio (Ratio) Float op('compress').par.Ratio

Default:

4

Range:

1 to 20

Knee (Knee) Float op('compress').par.Knee

Default:

6

Range:

0 to 24

Attack (Attack) Float op('compress').par.Attack

Default:

10

Range:

0.05 to 200

Release (Release) Float op('compress').par.Release

Default:

120

Range:

5 to 2000

Autorelease (Autorelease) Toggle op('compress').par.Autorelease

Default:

Off

Options:

Off, On

Makeup (Makeup) Float op('compress').par.Makeup

Default:

0

Range:

-24 to 24

Automakeup (Automakeup) Toggle op('compress').par.Automakeup

Default:

Off

Options:

Off, On

Mix (Mix) Float op('compress').par.Mix

Default:

1

Range:

0 to 1

Detect (Detect) Menu op('compress').par.Detect

Default:

peak

Options:

peak, rms, hybrid

Rmsms (Rmsms) Float op('compress').par.Rmsms

Default:

10

Range:

1 to 100

Link (Link) Menu op('compress').par.Link

Default:

linked

Options:

linked, unlinked, pairs

Usesidechain (Usesidechain) Toggle op('compress').par.Usesidechain

Default:

Off

Options:

Off, On

Schpf (Schpf) Float op('compress').par.Schpf

Default:

80

Range:

20 to 1000

Listen (Listen) Toggle op('compress').par.Listen

Default:

Off

Options:

Off, On

Lookahead (Lookahead) Float op('compress').par.Lookahead

Default:

0

Range:

0 to 10