Why Sound Waves - Why NOT just data?

[Mech_Fire]

yup as Compro01 has pointed out the system aims to use analog control over digital control, granted in most systems some DAC/ADC (digital to analog conversion/ Analog to digital conversion) needs to take place this is not always the case as some motors like stepper motors (more expensive then a simple motor) are driven from a digital signal. If any one is not sure of the area or is interested I would suggest spending a small amount of time looking into the differences between analog and digital control systems and sensors. If you do explore this area and take into account the design of the peachy in the process you will see how cleaver the idea of using an analog signal in this context actually is. One final thing I would like to point out (or make more confusing ) for anyone who is not used to this subject is that the question here is slightly misleading, the question asked about using a sound wave over data, a sound wave (an analog signal) is carrying data, I assume that the OP meant the data in this case to be a digital signal, any encoded signal is carrying data, even a hand gesture or facial expression .