I have some Vexta PK569 5-phase motors & Vexta drives. Let me tell you, the difference between a 5-phase and a 2-phase motor is amazing. The 5ph motors are absolutly smooth as silk, there is none of the resonance/buzzing that you get with a 2ph stepper. They are also nearly silent until you get up to about 600+ RPM, and then they make a high pitch zhhhhiiiiiiiinnngggg. My Vexta documentation also says 5ph steppers have more torque when you 1/2 step them vrs full step.
I will try to make a short video of a 2ph stepper motor winding up, and a 5-phase so you can see & hear the difference.
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