Sweep is an effect that filters.
Utilizing the same algorithms that sound designers use to create shephard tones / risset filters, Sweep uses a bunch of filters to make your sound feel like it’s rising (or falling) endlessly.
In Sweep’s case, the left and right channels can be split and controlled separately for a more complex, stereo aware sweeping effect.
Sweep is available as a free to download VST / AU plugin for both Windows and Mac platforms.