Synapse Audio Software is a German developer of software synthesizer plug-ins, founded by Richard Hoffmann and based in Rosengarten, Germany. The company began in November 1998 under the name Sonic Syndicate, rebranding to Synapse Audio in 2002 with the release of Orion Platinum, a standalone music production package with a multitrack sequencer and pattern-based workflow.

Synapse Audio is best known for DUNE 3 (Differential Unison Engine), a polyphonic synthesizer combining VA/subtractive, wavetable, and FM synthesis that has become popular among electronic music producers. The Legend HZ, developed in collaboration with film composer Hans Zimmer and sound designer Kevin Schroeder, is a Minimoog emulation featuring 200 factory presets co-designed by Zimmer. Other products include Obsession, an Oberheim-style poly-analog synth emulation; Proxima, modeled after the Sequential Circuits Prophet-600; Hydra, a multi-model FM synthesizer; and Antidote, a Rack Extension for Propellerhead Reason.

The company's plug-ins are available in VST, VST3, Audio Unit, and AAX formats for macOS and Windows, targeting professional music producers and sound designers working in electronic music, film scoring, and sound design.