ahi va....curious plug....no sé si ya saldría, pero no me suena:
http://www.sadglad.com/SV/Super-Volu.html
McDodo's Super-Volu Remove the change in volume caused by other Plugins.
This help to determine the impact they have on sound character, isolated from their effect on volume.
Super-Volu have two parameters Port, and Type. Port can be 1-16 and has nothing to do with midi. It allows you to connect the Before unit to the After unit.
Type can be 'Before', or 'After' Insert two instances of Super-Volu as INSERT effects in a channel, one before the Plugin/s that you want to test, and one after.
Set them both to the same port ( for example 1)
Set the one which is before to "Before", and the one which is after to "After".
You will see that the effects between the two instances of Super-Volu have no effect on the volume.
If you want to test more effects or channels, then insert another Super-Volu pair, and set the Port to a different value than the first pair.
Note: If you want you can also use this plugin to create an effect where the volume of one channel of audio modulates the volume of another channel. to do this use the same port number for both channels.