What is it?
It is an AudioUnit effect plug-in for MacOS X with currently one effect unit embedded. It is not a VST plugin and will probably never be.
What does it do?
Rumblence:pure is an audioeffect with 2 multimode filters, a waveshaper and a modular routing architecture. it generally splits the signal into two lines (1 and 2), first of which contains the difference between waveshaped signal and signal (the shaping only, if you want so), second the pure signal. It can be selected, how the two streams are mixed: additive, subtractive, multiplied (like ringmodulation) or one line only. Filters can be applied at several locations within the stream.
To install drag file/bundle RumblenceAU.component to this location:
In your audio software it should show up as insert effect under:
Freeware by Urs Heckmann (u-he)