Originally Posted by askman
if you look at the KK's test, biggest thing we do notice about the esc power ramp is this.
turnigy esc takes about 8 clock cycle to go from 0 to full throttle. which means for your 25% change, it take 3 cycles to effect full change. since the cycle is totally depended upon frequency, at 50 hz, 3 cyc is 60ms while at 400hz, it is 7.5ms. anything less than about 10% throttle change, it will happen in 1 cycle. Now, I believe simonk's firmware actually take this ramp out, which means power change is much quicker. I believe this is the biggest reason for better performance.
Just because the ESC does it's speed change in 7.5ms or less if modified, doesn't mean the motor and prop are going to do theirs. There is not an infinite supply of current to accelerate the motor/prop instantly by 25%. You need to measure how fast a given motor prop combination can accelerate/decelerate. I would be surprised if would keep up with an ESC.