# Octave Band Frequencies

## Octave and 1/3 octave band frequencies

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 Bandslisten to the sound! - touch and click the frequency below! | ||
---|---|---|

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 Bandslisten to the sound! - touch and click the frequency below! | ||
---|---|---|

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 *20 ^{o}C*.