Ardura, an independent developer and trance producer, has just released a free, open-source synth called Actuate.
Actuate is a subtractive synthesizer, a sampler, and a granulizer all at once made in Rust. While it can be scary to look at because of its cluttered UI, it does deliver a very nice sound and has a lot of interesting features to offer.

It certainly doesn’t look like a finished and professionally clean product, but it should be praised for the generosity of the developer and his contribution to the audio community.
The conceptual design behind Actuate is quite unique, too.
The audio generators are three and logically divided in the interface into three different sections.
The first is the oscillator section, where you can find 12 oscillator shapes to choose from.
These vary from the standard Sine, Triangle, Saw, Ramp, Square, Pulse, and Noise to the more esoteric WSaw, SSaw, RSaw, RASaw, and RSquare.
For instance, SSaw is a custom sawtooth waveform with a little variance for a shimmery sound, while WSaw sounds crispier due to some noise variance.
The second generator section hosts a sampler with features like pitch shifting or resample stretching.
It also supports single-cycle waveforms for wavetable-like behavior.
The third and final generator is called Granulizer, basically hosting granular synthesis, with controls over the ADSR and crossfading between grains.
Any generator can go to any filter hence the sound design possibilities are expanded.

There are included 2 SVF Filters, a VCF-inspired filter, and Tilt-inspired filters that can be configured in parallel, serial, or bypassed.
You can choose from seven different algorithms or filter resonance approximations. This offers a variety of SVF (State Variable Filter) flavors, which is great for sound design purposes.
Some are approximations of classic filter designs like the Moog Ladder filter or the TB-303 squelchy LP.
Others are original designs created by the developer for you to explore and test.
Actuate also features 10 different FXs for post-processing, 3 LFOs, 2 Pitch Envelopes, and 4 Modulators that can be assigned to various destinations.
It reminds me a bit of the past freebie Halo 2 Lite by DHplugins in terms of audio architecture.
It is available for macOS, Windows, and Linux as a VST 3 and CLAP Plugin.
Download: Actuate (FREE Open-Source)
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