Audio Sample Rate and Bit Depth

Uncompressed audio quality is usually dependent on the sample rate and bit depth that it was sampled with. Lets me first explain what these are:


When you record sound into the PC it is broken up into a series of slices. These can be likened to the framerate of a video file, each moment in time is frozen and the information about it is recorded. In the same way, each audio slice represents a number that defines how high or low the audio is at that moment in time. These slices are called samples and the number of samples per second is measured in Hertz (Hz).

Bit Depth

A 'Bit' is a standard storage size used by your computer just like kilobytes and megabytes, it is actually the smallest unit of storage. Each bit can define itself as on or off (1 or 0). Eight bits make a byte, 1024 bytes make a kilobyte (1K) and 1024K make a megabyte (1 MB).

Going back to our video analogy, if the Samplerate is how many "frames" the audio has, then the bit depth is how large the frames are, the resolution or the amount of memory allocated to each frame. The large the bit depth the more possible amplitudes each audio 'slice' can have. Eight bit audio uses 256 amplitudes, 16-bit allows 65536 and 24-bit can have 16 Million!