An Introduction to Music Technology

Chapter 6: Digital Audio Data

Sampling Rate Example (song excerpt) [30 sec. YouTube video]—a song excerpt at 44.1 kHz, 22.05 kHz, and 11.025 kHz. Listen for the reduced high frequencies as the sample rate drops. The maximum frequency in each is the Nyquist Frequency, which is half of the sampling rate. Special thanks to Phil Calvert for creating the original examples.
Sampling Rate Example (snare hits) [10 sec. YouTube video]—opening snare hits at 44.1 kHz, 22.05 kHz, and 11.025 kHz. Listen for the reduced high frequencies as the sample rate drops. Special thanks to Phil Calvert for creating the original examples.

Sample Resolution Example (song excerpt) [30 sec. YouTube video]—a song excerpt at 16 bits and 8 bits. Listen for the constant low-level noise in the 8 bit example. Special thanks to Phil Calvert for creating the original examples.
Sample Resolution Example (fade out) [30 sec. YouTube video]—a fade out at 16 bits and 8 bits. Listen for the distortion in the fade out of the 8 bit example. Special thanks to Phil Calvert for creating the original examples.

A comparison of two audio loop types undergoing tempo change

Audio Loop Tempo Changes [1.5 min. YouTube video]—The same loop in Wav and Rex format is played first at the original tempo of quarter=130, then at quarter=100, and finally at quarter=40. As the Wav version is slowed down, artifacts are introduced thus degrading the sound. As the Rex version is slowed down, gaps and silences appear between the slices, but the slices themselves sound fine. In both cases modest tempo changes sound OK and extreme tempo changes sound unnatural.