Frequency band

Professional Definition

A set of frequencies contained between two boundary frequencies: lower ($f_d$) and upper ($f_g$).

In acoustic engineering, this band defines the range of the spectrum of the signal analyzed or processed by the device. The bandwidth is the difference between these boundaries. In sound analysis, the division into octave bands or third-octave bands (1/3 octave) is most commonly used, allowing for a precise determination of the absorption characteristics of materials or the insulation of partitions as a function of frequency.

Acoustics in Simple Words

Imagine the full range of sounds – from the deepest bass to the highest squeaks – as a large, infinite piano keyboard. The frequency band is simply a specific segment of this keyboard that interests us at the moment. It could be, for example, just the bass section (low notes) or only the highest keys. When we talk about the frequency response of headphones, it is information about which part of this “keyboard” they can faithfully reproduce – from which to which key.

Summary

The frequency band is a fundamental concept that defines the operational range of acoustic phenomena. It allows engineers to divide complex noise into smaller fragments, making it easier to select appropriate soundproofing materials and adjust the acoustics of rooms.