Bit depth

In general, bit depth refers to the number of bits available for representing a "unit" of some digital data. For example, bit depth may be used to describe how many bits are available per pixel in an image: 1-bit would be 2 colors, black and white. (A QR code would be a real-life example.)

In audio engineering, bit depth refers to the number of available bits for each sample.¹ A larger bit depth means that the audio signal level's true value can be represented more accurately.² That is to say, a larger bit depth will lead to a larger dynamic range.

Each additional bit adds about 6 dB to the dynamic range. Thus, a 16-bit resolution gives a 96 dB dynamic range and a 24-bit resolution gives a 144 dB dynamic range. This value also represents the signal-to-noise ratio (SNR). That is, 24 bits gives an SNR of 144 dB.³

A depth of 16 bits is sufficient for listeners, but a depth of 24 bits is recommended when working with audio as the noise floor may be increased when working with tools like compression.⁴

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