418 Hz Wavelength

How Long Is a 418 Hz Wavelength?

A 418 Hz sound wave has a wavelength of 0.82 meters, 82.11 cm, 2.69 feet (2 feet and 8.33 inches) or 32.33 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 = 418 Hz
which gives a wavelength λ of 0.82 meters, or 2.69 feet.

418 Hz Wavelength Depending on Temperature

The speed of sound in air depends on temperature. Here is how the wavelenght of a 418 Hz sound wave will vary according to temperature:

Temp (°C) Temp (°F) 418 Hz wavelength (cm)418 Hz wavelength (in)
-40-4073.225528.8289
-35-3174.006529.1364
-30-2274.779429.4407
-25-1375.544329.7419
-20-476.301630.0400
-15577.051430.3352
-101477.794030.6276
-52378.529630.9172
03279.258431.2041
54179.980531.4884
105080.696231.7701
155981.405532.0494
206882.108832.3263
257782.806032.6008
308683.497532.8730
359584.183233.1430
4010484.863533.4108

418 Hz Half Wavelength and Standing Waves

The half wavelength of a 418 Hz sound wave is 0.41 meters, 41.05 cm, 1.35 feet (1 feet and 4.16 inches) or 16.16 inches when travelling in air at 20°C (68°F).

Modes (or standing waves) will occur at 418 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 418 Hz wavelength = 0.82 meters, or 2.69 feet in air at 20°C (68°F).

418 Hz Standing Waves Distances

n Distance (m) Distance (ft)
10.411.35
20.822.69
31.234.04
41.645.39
52.056.73

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

Given the relatively small 418 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 418 Hz To ms

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

Because a 418 Hz wave will ocillate 418 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 = 418 Hz

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

1 / 418 Hz * 1000 = 2.39 ms.