I was looking at ESC settings for whoops/toothpicks and have seen how the 48KHz JESC firmware can increase flight time. Why is this? Thanks!
To clarify, the 48kHz is NOT running on the gyroscope or the FC firmware. What 48kHz is referring to is the PWM Frequency in the ESC, namely the frequency at which the power MOSFETs on the speed controller switch on and off in order to provide power to the brushless motors and therefore thrust to the craft. The reason in whoops and small/light craft 3" and smaller will see a flight time improvement is that the RPm ranges these crafts fly at, the switching down-time at lower PWM frequencies means the motor/ESC is having very small active braking events in the switching cycle, then overcompensating by driving higher throttle values to compensate (both of which cost energy).
In some cases, 96kHz will also work very well, although this is often limited to smaller whoop class quads, and I would caution against it on specific instances where the ESC design has a higher dead time value because these tend to suffer failures more often at higher PWM frequency when pushed hard.