Software synthesizers for Linux

TiMidity++, originally and still frequently informally called TiMidity, is a software synthesizer that can play MIDI files without a hardware synthesizer. It can either render to the sound card in real time, or it can save the result to a file, such as a PCM .wav file.

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).