occurrence of spurious frequency components due to the presence of an input
signal to the systemís ADC (analogue to digital converter) whose frequency
was greater than 1/2 the sampling
If S is the sampling rate and F is a frequency higher
than 1/2 the sampling rate, then a new frequency will be produced FA where
FA = S - F.
If SR = 44.1 Khz and F = 28 KHz we will get a new signal
(FA) of 16.1 KHz included in the sound file.