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Compressor Multi (Multi Band)

Refer to Compressor (Single Band) for common theory and options. The normal compressor acts over the entire frequency spectrum. The multi-band allows us to distinguish three frequency ranges (low, med and high) on which to intervene separately and in a more sophisticated way. In other plugins there are four bands instead of three, but we can make very precise adjustments so the three present are enough because they are not fixed. Finally the value of the three corrections are added together in the Output.

The three bands and their range (adjustable as desired) are shown in the frequency graph visible below (Bandwidth:). As a first step you choose the band and adjust its range in the Bandwidth graph, then you go to adjust the compression in the top level graph. In this graph we can copy/paste the curve in the other bands via RMB; so we have a similar basis on which to make the adjustments.

In figure 10.14 we can see the three bands; the one currently active (Current band: 2) presents the waveform of the sound signal. The interval goes roughly between 300 Hz and 4000 Hz, the edges are vertical because the stepness is set to zero. So we have a clear separation between the bands, but by varying the slope we can have some overlapping of the bands for smoother effects. In the top level graph we can see the yellow curve of the active band, but we can also see in the violet the soft lines of the curves of band 1 and 2.

Figure 10.14: GUI of configuration for Compressor Multi plugin

Solo
  : brings only the active band to the Output, silencing the others. So we can make more precise adjustments without listening to the whole effect.
Bypass band
  : In contrast to Solo, it only brings the sound signals of the two inactive bands to the Output.
Freq range
  : is used to set bandwidth limits. You act separately on the left and right edge.
Steepness
  : varies the slope of the edges of the band range. Creates some overlap in the band boundaries.
Channel
  : is the equivalent of the Trigger option in Compressor (single band). Allows you to choose the channel or track to act on.
Window size
  : Determines the number of samples used in the compression calculation. The more they are, the higher the quality of the result, but the more CPU usage.