Nyquist's sampling theorem says "if you have a signal that is perfectly band limited to a bandwidth of f0 then you can collect all the information there is in that signal by sampling it at discrete times, as long as your sample rate is greater than 2f0".
The higher the sample rate the more small/fast fluctuations in the shape of the signal will be captured in a digital format - at the cost of having to use more storage space to store all of the extra numbers.
The Nyquist theorem, which exactly describes the relationship between the sampling rate and the spectrum of the stored audio. According to the Nyquist theorem, the highest frequency which can be accurately represented in a digital audio format is exactly half of the sampling rate. This cutoff frequency at half the sampling rate is called the Nyquist frequency.
For example, if a digital recording system is running at a sample rate of 44,100 Hz (the CD standard) then the highest frequency that system can accurately capture will be 22,050 Hz - exactly half the sample rate. As another example, if a digital recording system was running at a sample rate of 22,050 Hz (common on computers during the late 1980s and early 1990s) then the highest frequency it could accurately represent would be 11,025 Hz.
Notice how this figure is considerably lower than the 20 kHz typically cited as the upper limit of human hearing. A recording/playback system at 22,050 Hz would be missing most of the brilliance register of the audible spectrumNyquist's sampling theorem says "if you have a signal that is perfectly band limited to a bandwidth of f0 then you can collect all the information there is in that signal by sampling it at discrete times, as long as your sample rate is greater than 2f0 ".
The higher the sample rate the more small/fast fluctuations in the shape of the signal will be captured in a digital format - at the cost of having to use more storage space to store all of the extra numbers.
The Nyquist theorem, which exactly describes the relationship between the sampling rate and the spectrum of the stored audio. According to the Nyquist theorem, the highest frequency which can be accurately represented in a digital audio format is exactly half of the sampling rate. This cutoff frequency at half the sampling rate is called the Nyquist frequency.
For example, if a digital recording system is running at a sample rate of 44,100 Hz (the CD standard) then the highest frequency that system can accurately capture will be 22,050 Hz - exactly half the sample rate.
As another example, if a digital recording system was running at a sample rate of 22,050 Hz (common on computers during the late 1980s and early 1990s) then the highest frequency it could accurately represent would be 11,025 Hz. Notice how this figure is considerably lower than the 20 kHz typically cited as the upper limit of human hearing.
A recording/playback system at 22,050 Hz would be missing most of the brilliance register of the audible spectrum