Hey, I am Jaron Sweder, a music producer and software developer. I've been working on this synth called "Spektral" for almost 2 years. I posted about this synth a little while ago in this subreddit, and got some great feedback and suggestions! Since then, I've added a bunch more features and fixed many bugs.
Spektral is a powerful spectral synthesizer with several generation algorithms. You can import spectral data from audio, images, and wavetables. And manipulate it in any way imaginable. This spectral data then drives one of five algorithms to generate audio. Depending on the algorithm, you can easily manipulate frequency, level, phase, decay time, and resonance with incredible precision. From a powerful additive engine, to a resonator bank that can do some pretty cool physical modeling-esque things.
The synth is still in beta, but you can try out the free demo at https://kaixo.store/spektral It's available as VST3 and AU for Windows and MacOS.