Calf EQ Mid/Side

Im currentlys starting to get into mid side processing.

At the moment im trying to do some mid side EQ.

calf plugins you can select what each eq filter is doing. On which im sure is just normal both channels. then theres L, R. Mid and Side.

Everything works as expected except for side which appears to do nothing.

Is there some special routing i need to do to have side working?

Maybe i dont quite understand mid/side yet. Im basically using it on a vocal track which is mono. the calf plugins which are stereo only make my tracks stereo.

In M/S-processing the side contains the difference of both stereo tracks. If you apply it on a mono track, the side-track simply contains silence.