1. Analog-to-Digital Conversion (ADC):
- The first step involves converting the continuous analog sound signal into a discrete digital format.
- This is done using an analog-to-digital converter (ADC), which measures the amplitude of the sound signal at specific, equally spaced time intervals.
- The sample rate determines how frequently the amplitude is measured, typically in samples per second (SPS) or kilohertz (kHz).
2. Quantization:
- Each sampled amplitude value is then quantized, which means it's assigned a discrete numerical value.
- The number of bits used for quantization determines the resolution of the digital audio. A higher number of bits allows for more precise representation of the original sound.
3. Sampling Rate:
- The sampling rate, as mentioned earlier, determines how frequently the sound signal is sampled.
- Higher sampling rates result in more samples per second, capturing more detail and preserving higher frequencies in the sound. However, higher sampling rates also require more storage space.
4. Bit Depth:
- Bit depth refers to the number of bits used to represent each sample.
- Common bit depths include 8-bit, 16-bit, 24-bit, and higher. Higher bit depths provide better dynamic range and reduced quantization noise.
5. Encoding and Compression:
- Once the sound is sampled and quantized, it needs to be encoded into a digital format for efficient storage and transmission.
- Various audio file formats, such as WAV (uncompressed), MP3, AAC, FLAC, and others, use different encoding and compression algorithms to store the digital audio data compactly.
6. Storage and Playback:
- The digitally encoded audio data can be stored on various storage devices, such as hard drives, solid-state drives, optical media, or streamed over networks.
- To play back the digital audio, a digital-to-analog converter (DAC) is used to convert the discrete digital signal back into a continuous analog waveform that can be amplified and played through speakers.
Overall, the process of sampling and storing sound in digital form allows continuous analog audio to be represented in a discrete, numerical form that can be processed, manipulated, stored, and reproduced using digital devices and technologies.