XPNDR is an audio expansion effect that expands the dynamic range of a signal. Effectively the opposite of compression, the expander affects the signal below the threshold.
The ratio sets the severity of the expansion. For example, if the ratio is 2:1 and the signal falls below the threshold by 6dB, it will be reduced to 12dB below the threshold. A higher ratio accentuates the dynamics of the signal.
The threshold sets the decibel level under which the expander begins “expanding.” The higher the value the more sensitive the effect will be.
The attack determines how fast the expander affects the signal falling below the threshold.
Once the expander begins affecting the signal it stays on for a specified period of time set by the release.
Use the gain to compensate for signal reduction from the expander. Switch the bypass to ensure the signal is staying at an appropriate level.
To use XPNDR with a sidechain input, route the signal used as your reference into the upper left sidechain input port. The effect will use the level of the sidechain input signal to manipulate the intensity of the effect.
A technique often employed with sidechain-enabled expanders is to route a pad through the effect and route a high-hat into the sidechain. Use this to add some depth and texture to once plain pad sounds.