Cairo Glue

• Threshold (-40.0 dB to 0.0 dB): where the compression starts. For glue, set it so the gauge moves 1 to 4 dB on the loud parts.
• Ratio (1.0:1 to 10.0:1): how firmly the level above the threshold is held. 2:1 glues gently; 4:1 and above takes control.
• Knee (0.0 dB to 12.0 dB): a soft knee fades the compression in around the threshold instead of switching it on, so it is harder to hear working.
• Attack (0.10 ms to 100 ms): how fast it grabs. Slower settings (10 to 30 ms) let the punch of the drums and the bite of the consonants through; faster settings tame peaks.
• Release (10 ms to 1.00 s): how fast the level comes back after the compressor lets go.
• Auto release (on/off): program-dependent release. After a short peak the level recovers quickly; after a long loud passage it recovers slowly, so the mix does not pump. Measured: about 150 ms after a 30 ms burst, about 840 ms after 3 seconds of compression.
• Makeup (-12.0 dB to +12.0 dB): level after the compressor, to match what you hear with Bypass.
• SC HPF (Off to 1.00 kHz): a high-pass filter on what the compressor listens to, never on what you hear. Turn it up and the kick and 808 stop pushing the vocal down. In our test, 300 Hz took a 50 Hz kick from 13.7 dB of gain reduction to none.
• Stereo link (0 % to 100 %): at 100 % both channels always get exactly the same gain, so the stereo image and the mono sum cannot change, and a sound that is out of phase between left and right is compressed exactly as much as the same sound in the centre. Lower values let each side compress on its own.
• Detector (RMS or Peak): RMS follows loudness and is the smooth choice for glue; Peak catches every transient for tighter control. Both read a steady tone at its peak level, so the threshold means the same in both, and the Peak detector holds each peak for 12 ms so bass notes do not make the gain ripple.
• Mix (0 % to 100 %): parallel compression. Blends the dry and the compressed signal, which are sample-aligned at every setting, so there is never any phasing.
• Bypass and A/B: click-free bypass, and two settings slots to compare. Preset changes while the song plays do not click either.

• Gain reduction gauge: reads like a car speedometer, with the exact number under the needle. The scale gives the most room to 0 to 6 dB, where glue lives; past 6 dB it turns red and a warning lamp lights, because that is where compression starts to sound squashed. In our tests the needle showed the applied gain reduction with no measurable error.
• 10-second history: input peaks behind output peaks, so you see exactly which hits the compressor touched, and the gain reduction underneath with anything over 6 dB in red.
• True peak (ITU-R BS.1770, 4x oversampled), RMS, crest factor and GR max readouts.
• Stereo image / mono check: input and output correlation, and the largest gain difference between left and right. 0.0 dB and "Image locked" mean the compressor cannot move, narrow or widen your mix.
• Input / output meters: peak and RMS for each side, with a held max-peak number. They turn red only above 0 dBFS.

• Zero latency: no lookahead, 0 samples reported to your DAW.
• Gain only: no filters, delays or oversampling in the sound path, so no phase shift. Below the threshold the signal comes out bit for bit as it went in, and Bypass is bit-exact.
• Clean: harmonics under compression measured at -122 dBc on a 1 kHz tone and -83 dBc on a 100 Hz bass note with the Mix Glue preset.
• Light: under 1 % of one CPU core at 48 kHz stereo.
• Mono and stereo tracks, 44.1 to 192 kHz.

Download the zip from your account, close your DAW and run the Setup file. VST3 is always installed, and you can tick CLAP if your DAW supports it. If an earlier Cairo Glue is installed, Setup replaces it automatically. Then rescan your plugins: Cairo Glue is listed under M III D O. The installer isn't code-signed yet, so Windows may show an unknown-publisher notice. Choose More info, then Run anyway.