240 Hz Wavelength

How Long Is a 240 Hz Wavelength?

A 240 Hz sound wave has a wavelength of 1.43 meters, 143.01 cm, 4.69 feet (4 feet and 8.3 inches) or 56.3 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 = 240 Hz
which gives a wavelength λ of 1.43 meters, or 4.69 feet.

240 Hz Wavelength Depending on Temperature

The speed of sound in air depends on temperature. Here is how the wavelenght of a 240 Hz sound wave will vary according to temperature:

Temp (°C) Temp (°F) 240 Hz wavelength (m)240 Hz wavelength (ft)
-40-401.27534.1842
-35-311.28894.2288
-30-221.30244.2730
-25-131.31574.3167
-20-41.32894.3600
-1551.34204.4028
-10141.35494.4453
-5231.36774.4873
0321.38044.5289
5411.39304.5702
10501.40554.6111
15591.41784.6516
20681.43014.6918
25771.44224.7316
30861.45424.7712
35951.46624.8103
401041.47804.8492

240 Hz Half Wavelength and Standing Waves

The half wavelength of a 240 Hz sound wave is 0.72 meters, 71.5 cm, 2.35 feet (2 feet and 4.15 inches) or 28.15 inches when travelling in air at 20°C (68°F).

Modes (or standing waves) will occur at 240 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 240 Hz wavelength = 1.43 meters, or 4.69 feet in air at 20°C (68°F).

240 Hz Standing Waves Distances

n Distance (m) Distance (ft)
10.722.35
21.434.69
32.157.04
42.869.38
53.5811.73
64.2914.08
75.0116.42
85.7218.77
96.4421.11
107.1523.46
117.8725.80
128.5828.15
139.3030.50
1410.0132.84
1510.7335.19
1611.4437.53
1712.1639.88
1812.8742.23
1913.5944.57
2014.3046.92
2115.0249.26

Given the relatively large 240 Hz half wavelength, standing waves will occur at that frequency in small listening rooms.

You can try to minimze the room modes at 240 Hz by trying different speaker positions, listening positions or by placing bass traps. These can absorb frequencies as low as 63 Hz.

How To Convert 240 Hz To ms

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

Because a 240 Hz wave will ocillate 240 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 = 240 Hz

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

1 / 240 Hz * 1000 = 4.17 ms.