Apple Logic Express 8 - Manual (Page 241)

Chapter 10 Working With Instruments and Effects 241
The signal peaks of the side chain input (the sent instrument signal), combined with
the Threshold parameter of the plug-in, determine when the plug-in is triggered.
Some Side Chaining Examples
 A sustained pad sound is sent through a noise gate, which is triggered by a drum
track being used as the side chain input signal. This results in a rhythmic pad sound
which follows the signal peaks of the drum track.
 A noise gate inserted into a bass guitar channel is triggered by the kick drum track
via the side chain. This can tighten the timing of the bass guitar, as it follows the kick
drum signal.
 Side chains can also be used to blend a music mix with a voice-over. To achieve this,
the mix needs to be routed through a compressor which, in turn, is side chained,
using the voice-over track. In this type of setup, the music becomes softer when the
narrator is speaking, and louder, when not. The effect is also known as ducking.
Please note that in order for this to function, the Automatic Gain Make-up or Auto
Gain control (if applicable to the compressor plug-in) must be disabled.
Hiding and Showing Extended Parameters
Some Logic Express plug-ins may have additional parameters that don’t appear in the
Editor view (the graphical interface of the plug-in).
This is indicated by a disclosure triangle that appears at the bottom left of the plug-in
window.
If no disclosure triangle is visible, the plug-in has no additional parameters.
To hide or reveal the extended parameters:
m Click the disclosure triangle at the bottom of the plug-in window.