SpiralSynth Modular (or SSM) is an object orientated modular softsynth / sequencer / sampler. Audio or control data can be freely passed between the plugins, and is all treated the same. Data can also be fed back on itself for chaotic effects. LADSPA plugins are supported, and you can use them in the same way as any of the native plugins. Not having MIDI won't restrict what you can do. It currently uses the standard OSS/Free sound input/output (/dev/dsp), and should work on ALSA too. You can also render WAV files directly to disk.
