GAIN menu item
Under the GAIN menu item, you can set the level of the audio signal coming from the coupled transmitter (e.g. vocals via EW-D SKM-S or guitar via EW-D SK).
Under the GAIN menu item, you can set the level of the audio signal coming from the coupled transmitter (e.g. vocals via EW-D SKM-S or guitar via EW-D SK).

Unity gain refers to the configuration where the audio signal arriving at a device leaves the device with the same level.
Example: If you are using an EW-D wireless link instead of a guitar cable, with unity gain settings, the volume of the guitar in the guitar amplifier will be as high as it would be if using a guitar cable.
Possible unity gain settings: