Gate/Expander like ReaGate, but with ratio and range – Effects Forum

If you use Reaper you can check out the included General Dynamics JS plugin and draw your own curve to make any expander type you want. It’s a powerful tool that often gets overlooked in Reaper.

For VST’s though, there’s the free MCompressor that can also do custom transfer curves to make your own gate / expanders.

For something more traditional, there’s the legacy ToneBoosters Gate which is free now, and while it doesn’t have ratio control to make it an expander, it does have a range control.