"Mutator_uLFO_38+39" [mp3 removed]
MIDI notes trigger a modular synth patch. The monaural patch output is converted to stereo/autopan in the Mutator filter. The filter is in turn modulated by an envelope signal via the Mutator's "ext" input (the EG is triggered by an LFO from the uLFO module). This creates an echo sound but it's really just a pulsation as the wave diminishes. Two tunes were recorded and then overtracked.