What is the primary characteristic that differentiates analog audio signals from digital audio signals?

The primary characteristic that differentiates analog audio signals from digital audio signals is that analog signals are continuous and vary in voltage. Analog audio signals represent sound waves in a way that mirrors the original waveforms. This means that they can take on an infinite number of values within a given range; for example, the voltage in an analog signal changes smoothly, allowing it to replicate the nuances of sound, such as volume and pitch, in a continuous manner.

In contrast, digital audio signals do not vary continuously. Instead, they represent sound waves in a discrete manner, typically by sampling the amplitude of the waveform at specific intervals and then quantifying that value into binary data. This process results in a series of binary numbers that approximate the original sound.

Understanding this key characteristic helps clarify the foundational differences between analog and digital technologies, which is essential in various applications such as broadcasting, sound recording, and audio processing.