Compressor
From TANGOWIKI-TITAF
Compressor
A compressor is a dynamic range processor used in audio engineering. It reduces the volume of loud sounds and amplifies quieter parts (if desired), resulting in a more balanced and controlled audio signal.
Core Concept
The compressor monitors the incoming signal and reduces its level when it exceeds a defined threshold. The goal is to minimize the difference between loud and soft sections, making the audio smoother or more consistent.
Key Parameters
- Threshold
- The level (in dB) at which compression begins. Signals below the threshold remain untouched.
- Ratio
- Determines how much the signal is reduced once it crosses the threshold. A 3:1 ratio means that for every 3 dB above the threshold, only 1 dB passes through.
- Attack
- The time it takes (in milliseconds) for the compressor to start working after the signal exceeds the threshold. Short attack = quick reaction, long attack = natural transients.
- Release
- The time it takes to stop compressing after the signal drops below the threshold. A longer release results in smoother gain recovery.
- Make-up Gain
- Since compression often reduces overall volume, make-up gain brings the output level back up.
Typical Use Cases
- Vocal leveling in music production
- Preventing sudden peaks in live sound
- Adding punch or presence to drums and bass
- Loudness control in broadcasting and mastering
Variants
- Multiband Compressor – Processes different frequency ranges independently
- Limiter – A compressor with a very high ratio, used to prevent clipping
- De-Esser – Targets sibilant frequencies (typically 4–8 kHz) in vocals
Listening Tips
Well-set compression should be felt, not heard. Over-compression can make the sound dull, lifeless, or “squashed.”