What is sample rate?
Sample rate describes how many samples per second are used to represent an audio signal in sampled digital audio.
44.1 kHz means 44,100 samples per second
For PCM audio, a 44.1 kHz sample rate means each channel is represented by 44,100 sample values per second. A 48 kHz signal uses 48,000 samples per second.
Common sample rates
| Rate | Where you commonly see it |
|---|---|
| 44.1 kHz | Audio CD and music distribution |
| 48 kHz | Video, broadcasting and general multimedia |
| 88.2 / 96 kHz | Higher-rate recording and production workflows |
| 176.4 / 192 kHz | Specialist high-rate production or distribution |
Sample rate is not bitrate
Sample rate counts samples per second. Bitrate describes how much encoded data is used per second. A 48 kHz AAC file may have a bitrate of 128 kbps, 256 kbps or something else.
Sample rate is not bit depth
Bit depth describes the precision used for PCM sample values. Sample rate is the timing dimension; bit depth is the value precision dimension.
Common confusion
The first is sample rate; the second would be bitrate. They measure different things.
Source, mastering, processing and playback conditions still matter.
Related fundamentals
Quality context
Sample rate and the highest representable frequency
For a band-limited signal, the Nyquist-Shannon sampling theorem requires the sample rate to be greater than twice the highest frequency to be represented. A 44.1 kHz system therefore has a Nyquist frequency of 22.05 kHz; practical converters use anti-alias and reconstruction filters around that boundary.
Common audio sample rates
| Rate | Common context |
|---|---|
| 44.1 kHz | Audio CD and music distribution |
| 48 kHz | Video, broadcast, games and professional audio |
| 88.2 / 96 kHz | High-resolution recording and distribution |
| 176.4 / 192 kHz | Specialist high-resolution workflows |
| 352.8 kHz | DXD-family production workflows |
A higher number is not automatically a better recording or master. Source quality, processing and the playback chain still matter.