Reference Manual

303 Live Audio Effect Reference
22.7.1 Sidechain Parameters
The Compressor Device With Sidechain Section.
Normally, the signal being compressed and the input source that triggers the compressor are the
same signal. But by using sidechaining, it is possible to compress a signal based on the level of
another signal or a specific frequency component. To access the Sidechain parameters, unfold
the Compressor window by toggling the button in its title bar.
The sidechain parameters are divided into two sections. On the left are the external controls.
Enabling this section with the Sidechain button allows you to select any of Live’s internal routing
points (page 180) from the choosers below. This causes the selected source to act as the com-
pressor’s trigger, instead of the signal that is actually being compressed.
The Gain knob adjusts the level of the external sidechain’s input, while the Dry/Wet knob allows
you to use a combination of sidechain and original signal as the compressor’s trigger. With Dry/
Wet at 100%, the compressor is triggered entirely by the sidechain source. At 0%, the sidechain
is effectively bypassed. Note that increasing the gain does not increase the volume of the source
signal in the mix. The sidechain audio is only a trigger for the compressor and is never actually
heard.
Note that automatic Makeup is not available when using external sidechain.
On the right of the external section are the controls for the sidechain EQ. Enabling this section
causes the compressor to be triggered by a specific band of frequencies, instead of a complete
signal. These can either be frequencies in the compressed signal or, by using the EQ in conjunc-
tion with an external sidechain, frequencies in another track’s audio.
The headphones button between the external and EQ sections allows you to listen to only the
sidechain input, bypassing the compressor’s output. Since the sidechain audio isn’t fed to the