FabFilter has updated their Pro-G gate/expander plug-in to include “ducking” capability. Ducking works like an inverted gate—when the threshold is crossed, the signal itself is ducked down. Using its side chain input, a typical application of ducking is to automatically lower the level of a musical background track when a voice-over starts, and fade the level back up again when the voice-over stops. Ducking can also be used to achieve the popular “pumping” effects used in Electronic Dance Music.
I’ve used it to duck only the sound of the snare drum when it is (normally) heard in the overhead microphones on a live kit recording. I did this to remove the snare’s tone in the overheads when I replaced the snare drum track with samples.
FabFilter Pro-G is the best gate/expander I have in my Pro Tools 11 plug-in folder. It has a great GUI, expert side chain signal conditioning, and precise metering—you get a constant, graphical display parading across the front of the GUI. It shows continuously the action of the gate and its affect on the audio.
FabFilter Pro-G is available $174 MSRP download and works in both Windows and Mac OS X in 64 and 32-bit, VST and VST 3, Audio Units, RTAS, AudioSuite and AAX 64 Native.