696 Hz Wavelength

How Long Is a 696 Hz Wavelength?

A 696 Hz sound wave has a wavelength of 0.49 meters, 49.31 cm, 1.62 feet (1 feet and 7.41 inches) or 19.41 inches when traveling in air at 20°C (68°F).

The formula for the wavelenght is λ = c/f where:

  • c is the celerity (speed) of sound = 343.21 m/s or 1126.03 ft/s in air at 20°C (68°F).
  • f is the frequency = 696 Hz
which gives a wavelength λ of 0.49 meters, or 1.62 feet.

696 Hz Wavelength Depending on Temperature

The speed of sound in air depends on temperature. Here is how the wavelenght of a 696 Hz sound wave will vary according to temperature:

Temp (°C) Temp (°F) 696 Hz wavelength (cm)696 Hz wavelength (in)
-40-4043.977417.3139
-35-3144.446417.4986
-30-2244.910617.6813
-25-1345.370017.8622
-20-445.824818.0413
-15546.275118.2186
-101446.721118.3941
-52347.162918.5681
03247.600618.7404
54148.034318.9111
105048.464119.0803
155948.890119.2481
206849.312419.4143
257749.731219.5792
308650.146519.7427
359550.558319.9049
4010450.966920.0657

696 Hz Half Wavelength and Standing Waves

The half wavelength of a 696 Hz sound wave is 0.25 meters, 24.66 cm, 0.81 feet (0 feet and 9.71 inches) or 9.71 inches when travelling in air at 20°C (68°F).

Modes (or standing waves) will occur at 696 Hz in rooms where two opposing walls (axial mode), edges (tangential mode) or corners (oblique mode) are spaced by a distance d = nλ/2 where:

  • n is a natural (positive integer greater than or equal to 1)
  • λ is the 696 Hz wavelength = 0.49 meters, or 1.62 feet in air at 20°C (68°F).

696 Hz Standing Waves Distances

n Distance (m) Distance (ft)
10.250.81
20.491.62
30.742.43
40.993.24
51.234.04

We typically don't treat rooms for standing waves above 300 Hz.

Given the relatively small 696 Hz half wavelength, you can treat your room by using thick acoustic foam. This will absorb frequencies as low as 250 Hz, and all the way up to 20,000 Hz.

How To Convert 696 Hz To ms

A Hz (Hertz) is a cycle (or period) per second.

Because a 696 Hz wave will ocillate 696 times per second, we can find the time of a single cycle (or period) with the formula p = 1/f where:

  • f is the frequency of the wave = 696 Hz

The result will be expressed in seconds, so let's multiply by 1000 to get miliseconds:

1 / 696 Hz * 1000 = 1.44 ms.