ZynAddSubFX (also now called Zyn-Fusion) is a free and open-source software synthesizer for Linux, Mac OS X and Microsoft Windows. Version 3's new user interface was initially released under proprietary terms, but is now open source (though prebuilt binaries are still sold to fund development).[2]
For sound generation it has three hybrid synth engines that combine additive, subtractive, Fourier and other synthesis methods. No external samples are used to produce the sound; everything is done by synthesis. The synthesizer has effects like reverberation, echo, chorus, distortion, equalization and others, and supports microtonal tunings.[3][4]
The original author of ZynAddSubFX is Romanian programmer Nasca Octavian Paul.[5][6] The project was started in March 2002[3] and the first public version (1.0.0) was released on September 25, 2002.[7] Since 2009, the new maintainer is Mark McCurry.[8]
ZynAddSubFX combines several different methods of audio synthesis in order to create sounds: additive synthesis by the ADSynth engine,[3] subtractive synthesis by the SUBSynth engine,[3] and an original algorithm used to generate wavetables in the PADSynth engine.[9]
ZynAddSubFX was featured in the KVR One-Synth-Challenge contest.
In November 2013, Unfa released an album that was entirely made with ZynAddSubFX. Slavonic pagan ambient project Svitlo albums were created using ZynAddSubFX as synthesizer.