Rhizomatic Software Synthesis is the independent software company of Brian Clevinger, best known as the original designer of Absynth, which Clevinger first released through Rhizomatic in 2000 before it was picked up and distributed by Native Instruments. After his tenure with NI, Clevinger returned to releasing plugins under the Rhizomatic name.

The company's flagship product is Plasmonic, an MPE-capable software synthesizer that pairs physical-modeling resonators with subtractive synthesis and deep modulation to produce acoustically complex, expressive tones. Its follow-up, Synestia, reworks and extends the sound-shaping engines from Plasmonic into a multi-effect plugin built around physically-modeled resonators, dual filters, echoes, modulated delays, a flanger, distortion, a formant filter, and a multi-FX block called Sidebands.

Rhizomatic's plugins are released in VST3, AU, and standalone formats for macOS and Windows, and the brand has a niche reputation among sound designers and experimental electronic musicians for resonant, physically-modeled timbres and heavily modulated textures in the lineage of Absynth.

Rhizomatic has 1 product cataloged on Equipboard, including Synth Plugins.