Dust Equalizer is a basic channel equalizer, designed with the concept of less is more.
It comes with a pair of filters, pair of shelves and two mid-frequency bell filters. Using a fitting method to approximate analog-like response, each band keeps it's shape gracefully all the way to the highest of audible frequencies.
The filters have a standard Butterworth shape for flat passband without significant ringing. The shelves feature a custom, asymmetric design with a sharper knee towards the mid-frequencies and a more gradual shape towards the high or low frequencies.
The bell filters have classic log-symmetric shape, but feature gain-bandwidth interaction such that actual peak gain is higher for narrow bandwidth and becomes less as the bandwidth is increased. This maintains approximately even perceptible boost or cut as the width of the bells is varied.
Since 1.7.0 it no longer relies on any oversampling, and attempts to match the analog target also in terms of the phase-response.