SC Insert

Audio signal flow: Input > StereoInserts > Dynamics (Comp/Gate/Expander) > Dry/Wet > out
Sidechain signal flow: Input/ext. Input > Dynamics (Comp/Gate/Expander) SC input

Depending what InsertFx and Dynamic module (Compressor, Gate, Expander) is used, the achieved effect will be totally different.
Tip: when adjusting the Comp/Gate/Expander parameters, first turn the Dry/Wet knob on the right fully clockwise to 'Wet' to hear only the effect of the dynamic module.

Ducked Reverb on Vocals.  
In case you want reverb only to be heard in pauses, so that the vocals itself can be heard more clearly, proceed as following:
use a reverb as pre-dynamics insertFx, choose Comp mode, adjust threshold and ratio, and then attack and release time.

Fx only on loud passages.
Say you like to use a dominant fx like SSB Modulator or Pitch Shifter, but want it to be a bit more gentle.
After inserting it to a pre-dynamic insert slot, use Expander mode and adjust (foremost) ratio and threshold to get only the loudest parts affected by the fx.

Gated Reverb.
In this case, insert a Reverb fx into a pre dynamics insert slot, and select Gate mode.

Extern sidechain inputs (extL/R).
especially suited for use w/ Modular. You can get exceptional effects when using a Modular patch, maybe w/ tempo-synced LFO or Seq modules, for side-chaining one of the dynamic modules.  
note: if you want to use the extern SC inputs, the device cannot be used as an insertFx (in a mixer etc). Connect it separately in your Project window.

Download device: here  

SC Insert