As Voicecoil says, I'd take those figures with a pinch of salt.

Using older non-digital drives (actually pretty much all stepper drivers are digital, it's just digital refers to the fact that 'digital' drives have a processor), the drive simply brute forces the required current/voltage at the required intervals into the motor according to the drive settings.

The next step up in technology is morphing. Once a motor reaches a certain speed, microstepping the motor has no benefit, so the driver will gradually reduce it's stepping output until it's only outputting full steps. Most drives with morphing will allow you to adjust the point at which the morphing occurs, so the drive can be tuned to the motor and helps avoid resonance issues that will often cause stalling at certain speeds.

Then you have the latest digital drives, which combine the above, however they also monitor the current/voltage changes in the motor, and will adapt on the fly to avoid resonance and stalling issues, which means they can typically run the same motors faster.


Due to the nature of stepper motors, they resonate, and the key to running them fast is getting through the resonation zones, which is where digital drives excel.


Actually I've just had a thought, aren't the Easy Servos 3 phase?
Which means the bipolar (aka 2 phase) formulas don't apply, as 3 phase servos are better/smoother performing, however they are less popular as they're more expensive, and if you're looking for better performance than bipolar steppers, servos generally make more sense.