What does bit depth refer to in audio files?

• A. The sample rate of the audio.
• B. The number of bits of data in which the audio volume is measured in each clip/sample.
• C. The number of channels.
• D. The tempo of the audio.

Answer: (B)

Bit depth is about how many bits are used to describe each sample's amplitude. Each sample stores a numeric value that represents the instant sound pressure, and more bits mean more possible amplitude levels. With more levels, you can reproduce quieter and subtler differences more accurately, which increases the dynamic range and reduces quantization noise. For example, 16-bit audio has 65,536 possible levels per sample, while 24-bit audio has over 16 million. Because more data are stored per sample, higher bit depth also makes the file larger. This concept is separate from how often samples are captured (sample rate), how many channels the audio has (mono vs. stereo), or how fast the track plays (tempo).