Gluon: A Free Bus Compressor with Linked Controls
Gluon is a free bus compressor from nClear. Its distinctive feature is Gluon Map: a shared view for adjusting multiple instances without opening every compressor window in your session.
One view of several buses
Map shows settings and meters across compatible instances. You can adjust an individual compressor or make relative changes to several at once. It communicates control data; it does not route audio between buses.
That makes it worth investigating when a project has separate drum, synth and mix buses. A shared overview could help you notice where you have added compression repeatedly as the arrangement has grown.
Watch the official walkthrough
Compatibility and download
The developer lists macOS 12+ with VST3, AU and CLAP; Windows 10/11 with VST3 and CLAP; and a Linux build with VST3, LV2 and CLAP. DAW compatibility is marked experimental. Map requires instances of the same plugin module in the same host process.
The download form asks for an email address and offers a Download only option separately from newsletter signup. Gluon is free to use, with no activation or paid feature locks.