What happens to the sound quality if audio is sampled below the Nyquist frequency?

Sampling audio below the Nyquist frequency leads to problems in accurately representing the original sound wave. The Nyquist frequency is defined as half of the sampling rate, and it sets the minimum sampling threshold needed to capture all the necessary information without introducing distortion. When audio is sampled below this threshold, it cannot accurately reproduce high-frequency components of the sound. This can result in aliasing, where high frequencies are misrepresented as lower frequencies, leading to distortion and a loss of fidelity in the audio quality. Thus, the sound may lose clarity and detail, negatively impacting the listener's experience. This relationship between sampling rates and audio fidelity is a fundamental principle in digital audio processing.