1. Analogue sound wave
continuous signal
Smooth analogue wave
2. Sampling the wave
measure points per second
Original wave
Samples taken
3. Quantisation into digital levels
round to nearest bit-depth level
Possible digital levels
Stored digital values
Generated Binary Data
What is happening?
Sample rate controls how many times per second the computer measures the sound wave. A higher sample rate captures the shape more accurately, but creates more data.
Bit depth controls how many different values each sample can be rounded to. More bits means more possible amplitude levels, so the digital sound is closer to the original wave.
In this simulation, the binary shown is the digital value stored for each sample. Real sound files also include extra metadata, but this shows the core idea.