Limiter

The Limiter works much like a compressor but with one important difference: where a compressor proportionally reduces the signal when it exceeds the threshold, a limiter reduces any peak above the threshold to the threshold level, effectively limiting the signal to this level.

The Limiter is used primarily when mastering. Typically, you apply the Limiter as the very last process in the mastering signal chain, where it raises the overall volume of the signal so that it reaches, but does not exceed, 0 dB.

The Limiter is designed in such a way that if set to 0 dB Gain and 0 dB Output Level, it has no effect on a normalized signal. If the signal clips, the Limiter reduces the level before clipping can occur. The Limiter cannot, however, fix audio that is clipped during recording.

Figure. Limiter window.
  • Gain Reduction meter: Shows the amount of limiting in real time.
  • Gain slider and field: Sets the amount of gain applied to the input signal.
  • Lookahead slider and field: Adjusts how far ahead in milliseconds the Limiter analyzes the audio signal. This enables it to react earlier to peak volumes by adjusting the amount of reduction.

    Note: Lookahead causes latency, but this has no perceptible effect when you use the Limiter as a mastering effect on prerecorded material. Set it to higher values if you want the limiting effect to occur before the maximum level is reached, thus creating a smoother transition.

  • Release slider and field: Sets the amount of time, after the signal falls below the threshold level, before the Limiter stops processing.
  • Output Level knob and field: Sets the output level of the signal.
  • Softknee button: When active, the signal is limited only when it reaches the threshold. The transition to full limiting is nonlinear, producing a softer, less abrupt effect, and reducing distortion artifacts that can be produced by hard limiting.