Aaron Anderson recently launched Terrain, a free, open-source wave terrain synth instrument.
The plugin is available for MacOS, Windows, and Linux in VST3 and AU formats.
Anderson provided links to the Terrain installers for macOS and Windows in the video description for a YouTube demo of the plugin.

He is still working on the Linux installer, but he has provided a step-by-step guide for building the Linux version of the plugin on the GitHub page, aaronaanderson.
His GitHub page also hosts the repositories for the macOS and Windows versions of Terrain if you wish to build them yourself.
In wave terrain synthesis, sound is made via a 2D trajectory scanning over 3D terrain. The timbre of the sound produced is dependent on the parameters and shape of the trajectory and the scanned terrain.
The Terrain plugin allows you to mod the parameters of both the trajectory and terrain, opening up a lot of sonic possibilities.
The plugin calculates the terrain and trajectory per sample, which makes it heavy on computation resources.
Anderson has provided a YouTube demo and walkthrough showcasing the operation of Terrain, so you can get a feel for how all this works in practice.
The demo really displays how deep the customization options in Terrain are, and shows off a varied array of sounds that are possible from working with the plugin.
It seems like a pretty interesting and novel approach to creating a synth, and if you’re into tinkering and sound design, then I’m sure there’d be a lot to enjoy here.
Anderson has been working on the synth for quite some time, as he displayed the operation of a prototype of Terrain on YouTube all the way back in 2017.

The 2024 release is quite different, with a shiny new user interface and deeper customization for the terrain and modulation options.
Anderson spruiks the customization options available in Terrain in-depth on his GitHub.
The written walk-through is pretty detailed and provides insight into how the parameters combine to create different types of output from the plugin.
Anderson is a Californian dev that is quite active on GitHub. So far in 2024, he’s released six repositories.
His GitHub features several synth releases, as well as other plugins, libraries, and tools for creating plugins.
Download: Terrain (FREE)
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