Phasers tend to be either EXTREMEMLY simple or way too much, however with the Grand Orbiter 4 stage phaser, Earth Quaker Devices have a great balance of easy to understand control mixed with a bunch of possibility.
Rates 1 & 3 are simply fast and slow modes but Rate option 2 is interesting in how it'll freeze the phase at a point, players may be familiar with the concept of a "cocked" wah where-in a wah pedal is turned on but not rocked back and forward as we traditionally use a wah. Instead the player leaves it at a point producing an interesting thin or throaty tone. This is a very similar idea and a pretty cool one at that!
The sweep control curtails how high and low the phase reaches which is great for suiting it to your amp and guitar tones.