FL Studio Mobile

Compressor

Use the compressor to add punch to your kicks and weight to your basses. Compression is key to obtaining a loud and punchey sound.

To load presets tap the 'Default' (upper right) and choose from the Presets List.

Parameters

Compression is a form of automated gain (volume) control that reduces the dynamic range of sounds (difference between peaks and troughs in the waveform). When the input signal exceeds a predetermined threshold the rate of increase is slowed (or even stopped) beyond that point.

The art of setting a compressor is mainly in fine-tuning the magnitude, speed and timing of the automated gain changes so that the compression process does not introduce artifacts. How can reducing the amplitude peaks make the sound seem louder? To understand this we need to consider the way our hearing interprets the start (attack) and body (sustain) portion of sounds.

It happens that the attack (first ~10 ms) is used mainly to form impressions of timbre, clarity, crispness and punch, while the sustain contributes most to the perception of loudness. The sustained level of a sound is most important because loudness perception comes from an integration (averaging) of the previous 600-1000 ms. Attack transients (of very short duration) simply don't have as much weight (due to their short duration) as the sustain portion of the sound.

Lowering the amplitude of the peak transients, frees up headroom to raise the gain of the sustained portions of the signal (after compression), it is this step that increases loudness. However, as we alluded to earlier, compression represents a trade-off between dynamics and loudness.

  • Threshold - Sets the dB level at which the compressor kicks in. The threshold should be adjusted according to the relative input level and the type of audio material. Once the threshold level is reached, compression will start, reducing the gain of the input signal according to the current Ratio, Attack, Hold and Release settings. NOTE: The compressor has Automatic Gain Compensation so that as the threshold is decreased the Level is increased to make up for any lost gain. This will make the input sound louder as gains is decreased. You can compensate for this by reducing the Level.
  • Ratio - Controls the amount of compression (gain reduction) that will be applied to the signal once the threshold level is reached. Ratio denotes the difference in dB between input level and output level, i.e. how much the signal above threshold level will be compressed (or expanded, at ratios below 1:1). For example, a ratio of 4:1 means that when the input level increases by 4dB, the output level of the signal above threshold will only increase by 1dB. Ratios below 3:1 will be subtle. Although that will depend on the threshold too. Infinite means a hard-stop threshold or 'brick-wall' limiting. The signal will not be allowed to increase above the set level.
  • Attack - Controls the time it takes to reach full compression once the threshold level has been exceeded. Fast attack means that compression will be more or less instant. Slow attack results in the compression being gradually increased, allowing for more variations in the signal than a fast setting. Attack should be adjusted according to the type of audio material being used.
  • Hold - This is a delay before the compressor will release to no compression. Use it to smooth out the sound when high-frequency noises are setting off the compressor when you don't want it to. Rapid on/off compression can sound rough or distorted.
  • Release - Sets the time the compressor takes to stop acting after the level has fallen below threshold. Short release times will make the compression more flexible and able to adapt to the input signal, but can cause fast changes in gain that may sound unpleasant. Long release times produce a signal with a more even level and less distortion, but make it harder to maximize the overall compression because small variations in signal level will be ignored.
  • Level - Output level from the plugin, post-compressor. Apply +/- 20 dB of gain change.
  • Auto gain - When selected the output of the effect will automatically be increased to compensate for gain reductions caused by the compression process. This is also known as 'makeup gain'.
  • Metering:
    • Gain Reduction (GR) - Gain reduction Input vs Output caused by the compressor (dB). 0 dB means there is no compression active.
    • Input (IN) - Input signal level (dB).
    • Output (OUT) - Output signal level (dB)