The Control Freak combines the best of both types of conventional fan speed controller – giving you the quietness and smooth output of a hybrid type while giving you the controllability of a standard pulse width modulation (PWM) type. Standard fan speed controllers produce a spiky waveform which usually introduces a hum in the fan motor and can even reduce the fan’s lifespan. Hybrid fan speed controllers produce a nice smooth waveform but usually only have 4 or 5 available fan speeds. The Control Freak works in a completely different way – by adjusting the frequency of a smooth waveform. It gives you 90 available fan speeds (from 10% – 100%) which you can set yourself in manual mode, or the Control Freak can be put into automatic mode and it will find the right fan speed for you. You just set the temperature that you want and the Control Freak will do the rest.