Channels refer to the number and type of individual speakers contained in the device and are described by 2 numbers separated by a dot.

2. The first number refers to how many full-range speakers (speakers for the entire frequency range) the device contains, while the second refers to how many subwoofer-type speakers (speakers specialized for bass frequencies) it contains. For example, a speaker with 2.1 channels has 2 regular speakers and 1 subwoofer.

3. Almost all music tracks are stereo (for playback from at least 2 speakers), meaning they are made to sound different in each of the 2 channels to give the listener a sense of space. More speakers make this feeling even more realistic, and the presence of a subwoofer gives fuller bass.