Allpassphase: __exclusive__

Allpass phase is a subtle art. It is invisible on a standard frequency analyzer (which only shows magnitude), but it is audible to trained ears. It is the secret behind the "space" in your reverb, the "sweep" of your phaser, and the integrity of your crossover.

For a constant group delay (linear phase) across a band, you can design all-pass filters using prototypes — but note: an all-pass cannot be perfectly linear phase unless it’s a pure delay. allpassphase