Octave and 1/3 octave band frequencies

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The audible frequency range can be separated into unequal segments called octaves.

An octave higher is a doubling of the octave band frequency. Octave bands can be separated into three ranges - referred to as one-third-octave bands.

Octave Bands

Octave Bands
Lower Band Limit (Hz)	Center Frequency (Hz)	Upper Band Limit (Hz)
11	16	22
22	31.5	44
44	63	88
88	125	177
177	250	355
355	500	710
710	1000	1420
1420	2000	2840
2840	4000	5680
5680	8000	11360
11360	16000	22720

The "one-third-octaves" have been standardized for scientific instruments commonly used for tasks like to determine NC-criterion and similar.

Third Octave Bands

1/3 Octave Bands
Lower Band Limit (Hz)	Center Frequency (Hz)	Upper Band Limit (Hz)
11.2	12.5	14.1
14.1	16	17.8
17.8	20	22.4
22.4	25	28.2
28.2	31.5	35.5
35.5	40	44.7
44.7	50	56.2
56.2	63	70.8
70.8	80	89.1
89.1	100	112
112	125	141
141	160	178
178	200	224
224	250	282
282	315	355
355	400	447
447	500	562
562	630	708
708	800	891
891	1000	1122
1122	1250	1413
1413	1600	1778
1778	2000	2239
2239	2500	2818
2818	3150	3548
3548	4000	4467
4467	5000	5623
5623	6300	7079
7079	8000	8913
8913	10000	11220
11220	12500	14130
14130	16000	17780
17780	20000	22390

Wavelength

The wavelength depends on the speed of sound and can be calculated as

λ = c / f           (2)

where

λ = wavelength (m)

c = speed of sound (m/s)

f = frequency (s-1, Hz)

Sound velocity depends on the density of the air and the air temperature. Typical value for speed of sound is 343 m/s for temperature 20oC.