Finding free, good gate plug-in can be quite tough. One plug-in worth mentioning (and quite sophisticated) is AraldFX StormGate 1 – rhytmic gate effect that lets you shape audio with amplitude patterns (quite similar gate works in NI Massive synth).
Patterns can be freely drawn by hand (there are 16 different amplitude patterns) or with the aid of powerful drawing tools. The internal sequencer can be synchronized to the host song position and is capable of chaining (extending) the patterns. Within seconds you can transform a static pad into an exciting rhythmic part, create new rhythms from vocals, instruments, noises of any kind. It can also be used to simulate compressor sidechaining.
* Free drawn amplitude envelope.
* Powerful envelope drawing tools: Free, step, spike and exponential.
* Variable quantization grid.
* 16 patterns with variable length and chaining support.
* Steps of one octave or one octave triplet.
* Intelligent host loop support.
* Advanced synchronization.
* Swing on octaves and sixteenth.
* Volume controls for original and gated audio, with cross-fading control.
* 13 functions for editing the envelope (including randomizations).
If you’ll like StormGate1, you can consider upgrading to commercial StormGate3, which offers many additional features including multiband noise gating, filtering, envelopes recording.