Properties of the system

Linearity : No
The sum of two audio signals(vectors with amplitude and frequency of vibration), that is the air pressure created due to them is added linearly and hence the equivalent pressure is a like the pressure created due to the ‘sum‘ of the two signals An example: Two signals A*sin(2pa*t) and B*sin(2pb*t) are signals with frequencies ‘a’ and ‘b’ and intensities ‘A’ and ’B’ respectively produce certain variations in the air pressure with time Pa(t) and Pb(t) respectively then the equivalent pressure sensed by the system will be a sum equal to Pa(t) + Pb(t) with the net result being that the system gives a linear output since the part of the system is just represents the analog voltage data in digital form keeping its value unchanged or maybe scaling it by a factor at the most.

If the microphone output does not linearly varying with the air pressure then the above won’t hold though the system excluding the microphone would be linear again assuming that the sum of two input pressures would not be above the dynamic uppe limit in which case clipping (a phenomenon in which all the values above the highest are clipped to the highest value) takes place.

Causality : Yes
Clearly no input pressure variation till time t=0
the voltage waveform of the microphone is zero for all t<0 since there is no excitation. Thus no nonzero digits are given out at the output end since values of all the samples is zero. Also this may be said to be so since all real systems are causal.

Time Invariance :Yes Since the value of the output binary number depends only on the value of current input the system is time-invariant.

Stability : Yes Since the value of the output signal is just a scaled version of the input pressure of the air which in turn is always bounded, the system is a stable one.

Memory : No Also the sampler gives out only the output at only a given instant in time the system is memoryless. However systems cascaded to this one use zero order hold, linear approximation etcetera then the system(inclusive of the approximating system) no longer remains memoryless.

Invertibility : No Since the data of the values of the original signal between the sampling points is no longer known, the original waveform cannot be reconstruced however good the sampling mechanism be and hence the system cannot be invertible.

With respect to the other inputs the system, the sampling rate and the bit-depth is Causal, Time Invariant and Memoryless. The other two properties have no significance with respect to these inputs.

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