This is a collection of five variations on the same bell sound. The bell is being run through a modular synthesizer, with an emphasis on a module called the ADDAC601. The ADDAC601 is a filter bank. It divides the inbound audio into eight bands across the audio spectrum, and then allows those bands to be worked upon by any manner of inputs. In this case the inputs are a variety of LFOs, or low frequency oscillators, often working in combination. Sine waves and triangle waves and saw-toothed waves consort and, in turn, exaggerate the source audio. The LFOs put the overtones into overdrive. These five tracks, each more complex than the previous, are excerpts from a larger collection that accumulated after I added the ADDAC601 to my small modular synth rig. They explore incremental changes as LFOs pile up and the variations take on more internal complexity. Because they were recorded in sequence without pause, each retains echoing, refracted elements of the previous track.
The source audio is a bell recorded by Freesound.org
participant Sarana and uploaded for communal reuse on October 14, 2009. The source audio was pitched down a bit before being worked upon by the modular synth, and it also is run through a digital delay before hitting the ADDAC601. Here is the source audio, for comparison:
The track is licensed under this Creative Commons license:
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