问题
I have an input signal in time domain (that is, discrete 14100 signed integers per second).
If I reverse the polarity (signed-ness) of each value, will I not produce a destructive source-audio canceling signal?
回答1:
Destructive cancellation by simply reversing polarity will occur only if your total software/hardware/system/transducer delay time from your input signal to to your output signal to the point of cancellation is zero (or a very tiny percentage of the period of the highest frequency), and the frequency and phase response of the destructive transducer is absolutely flat.
e.g. only likely in fictional/theoretical models.
回答2:
Yes, Phase inversion (and summing the two) will cancel the signal, resulting in silence. Of course, you must mind numeric limits.
来源：https://stackoverflow.com/questions/10290862/by-reversing-the-polarity-of-a-time-domain-signal-can-i-cancel-the-source-audio