Sample Rate

In-Depth Explanation

What is a Sample Rate?

To understand Sample Rate, you must understand how microphones and computers work together. When you sing into a microphone, you create continuous analog sound waves. Computers, however, only understand digital data (1s and 0s). They cannot process a continuous, infinite analog wave.

To solve this, the audio interface takes rapid-fire "snapshots" (samples) of the audio wave as it passes by.

The Sample Rate is simply the speed at which the computer takes these snapshots, measured in Hertz (Hz) or kilohertz (kHz).

• A sample rate of 44.1 kHz means the computer is taking exactly 44,100 snapshots of the audio every single second.

The Nyquist Theorem

You might wonder, "Why 44,100? Why not 10,000 or a million?"

The answer lies in the Nyquist-Shannon sampling theorem, a fundamental law of digital audio. The theorem states that to perfectly capture and reconstruct a given frequency, your sample rate must be at least twice as high as that frequency.

Human hearing generally spans from 20 Hz to 20,000 Hz (20 kHz). According to Nyquist, to capture that upper limit of 20 kHz, we need a sample rate of at least 40 kHz.

The CD standard was set at 44.1 kHz (44,100 Hz) to comfortably cover the entire range of human hearing, plus a little extra mathematical "padding" (the Nyquist Frequency is 22.05 kHz) to allow the digital anti-aliasing filters to work properly without distorting the highest audible frequencies.

Common Sample Rates

• 44.1 kHz: The standard for CDs and almost all digital music streaming (Spotify, Apple Music). If you are producing music solely for streaming, this is often the only sample rate you need.
• 48 kHz: The standard for video and film production. If you are producing a film score, mixing audio for a YouTube video, or recording dialogue for TV, you must use 48 kHz to ensure the audio syncs perfectly with the video frame rates.
• 88.2 kHz and 96 kHz: Considered "High-Resolution" audio. It captures frequencies up to 48 kHz (well beyond what humans can hear or speakers can reproduce).
• 192 kHz: Ultra-high resolution, usually reserved for archival purposes or extreme audiophile recording.

The File Size Trade-Off

The primary drawback of recording at higher sample rates is file size and CPU strain.

Because you are taking more than double the number of snapshots every second, a session recorded at 96 kHz will take up roughly twice as much hard drive space as a session recorded at 44.1 kHz. Furthermore, your computer's CPU has to process twice as much data every time you add an EQ or Compression plugin.

(You can see exactly how this affects your storage using our Sample Rate Calculator).

Should You Record at 96 kHz?

This is a hotly debated topic among audio engineers.

• The Argument FOR 96 kHz: While humans cannot hear above 20 kHz, digital plugins (especially non-linear processors like saturation, distortion, and heavy compression) operate better at higher sample rates. Processing at 96 kHz significantly reduces "aliasing" (an ugly digital distortion that folds back down into the audible spectrum). Many engineers record at 96 kHz to give their plugins more headroom to sound "analog," then downsample the final master to 44.1 kHz for distribution.
• The Argument AGAINST 96 kHz: It destroys CPU limits. Unless you have a massively powerful studio computer, running a 100-track pop session at 96 kHz will cause the computer to crash constantly. For most home producers, recording at 44.1 kHz or 48 kHz at a high Bit Depth (24-bit) provides perfectly professional results.