13octavbånd

13octavbånd, or 13-octave band, is a term used in acoustics and audio engineering to describe a set of thirteen adjacent frequency bands that partition part of the spectrum into octave-spaced intervals. An octave band is defined by a bandwidth where the upper frequency is approximately twice the lower; thus a 13-band bank provides a coarse but meaningful summary of spectral energy across a given range.

Construction and use: In practice, a 13-octave band is realized as a filter bank, either analog or digital, with thirteen bandpass filters. The exact center frequencies and cutoffs depend on the applicable standard or device, but the bands are spaced roughly by a factor of two. The resulting data allow engineers to represent the spectral content of a sound with thirteen numbers rather than a continuous spectrum.

Applications: The 13-octave bank is used in sound level meters, spectrum analyzers, and environmental or industrial noise assessments, as well as in building acoustics and product testing. It is commonly used alongside finer sets such as 1/3-octave or octave-band analyses, offering a balance between resolution and data simplicity.

Limitations: Because octave bands are broad, they can obscure narrow-band features. For detailed analysis of tonal components, higher-resolution methods or full-spectrum analysis may be required.

See also: Octave band, 1/3-octave band, spectrum analysis, acoustic standards.