Instruments and Effects

72 Chapter 4 Dynamics
The Lookahead parameter allows the Limiter to look forward in the audio so that it can
react earlier to peak volumes by adjusting the amount of reduction. Using Lookahead
causes latency, but this latency has no perceptible effect when you use the Limiter as a
mastering effect, on previously recorded material. Set Lookahead to higher values if
you want the limiting effect to take place before the maximum level is reached,
creating a smoother transition.
Typically, you apply the Limiter as the very last effect in the mastering signal chain. In
this case, you use the Limiter to raise 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 (red gain line), the Limiter—
using its basic settings—reduces the level before clipping can occur. (However, the
Limiter cannot fix audio that was clipped during recording).
Multipressor
The Multipressor (short for multiband compressor) is an extremely versatile tool used in
mastering audio. It splits the incoming signal into different frequency bands (from one
to four), and allows you to apply compression to each band independently. After
compression is applied, the bands are combined into a single output signal.
The advantage of compressing different frequency bands separately is to apply a
higher amount of compression to the bands that need it without producing the
pumping effect often associated with high amounts of compression. Using the
Multipressor, you can apply higher compression ratios to specific frequency bands, and
therefore achieve a higher average volume, without causing audible artifacts.
Raising the overall volume level can result in a dramatic increase of the existing noise
floor. Each frequency band features downward expansion, which allows you to reduce
or suppress this noise. Downward expansion works as a counterpart to compression:
while the compressor compresses the dynamic range of the higher volume levels, the
downward expander expands the dynamic range of the lower volume levels. With
downward expansion, the signal is reduced in level when it falls below the threshold
level. This functions in a similar way as a noise gate, but rather than simply cutting off
the sound, it smoothly fades the volume using an adjustable ratio.