[PDF] Narrow-Band Frequency Analysis Using a 1/3-Octave-Band Real

What is the bandwidth of a third octave?

A third of an octave is a frequency band that is three times smaller than an octave band, so that an octave band logically comprises three third octave bands. Thus, the 1000 Hz third octave has a bandwidth of 891-1122 Hz.

How many 1/3 octave bands are there?

If we look at the 1/3-octave bands whose center frequencies cover the 50-Hz to 12,500 Hz (13.5 kHz, the center of critical band 24, is not a 1/3-octave-band center frequency) we find that there are 24 1/3-octave bands also. The bandwidths of the critical frequencies range from 100 Hz at low frequencies to 3500 Hz at high frequencies.

What are octave frequencies?

In Engineering applications, sound spectrums are usually represented in octave or one-third octave frequency bands rather than in narrow frequency bands. This frequency representation is linked to the perception of sound by a human ear and it allows a compression of the amount of information.

What is the center frequency of a 13th half octave band?

If we set/define the 13th half-octave band’s center frequency to be f ctr 1fctr 2. Conversely, all higher center frequencies for 1/2-octave bands can be defined from each other using the formula . Then for each center frequency, the 1/4-octave low (high) frequency for each 1/2-octave band are (respectively) given by the formulae 214f nn.