918 Hz Wavelength

How Long Is a 918 Hz Wavelength?

A 918 Hz sound wave has a wavelength of 0.37 meters, 37.39 cm, 1.23 feet (1 feet and 2.72 inches) or 14.72 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 = 918 Hz
which gives a wavelength λ of 0.37 meters, or 1.23 feet.

918 Hz Wavelength Depending on Temperature

The speed of sound in air depends on temperature. Here is how the wavelenght of a 918 Hz sound wave will vary according to temperature:

Temp (°C) Temp (°F) 918 Hz wavelength (cm)918 Hz wavelength (in)
-40-4033.342313.1269
-35-3133.697913.2669
-30-2234.049913.4055
-25-1334.398213.5426
-20-434.743013.6783
-15535.084413.8128
-101435.422613.9459
-52335.757514.0778
03236.089314.2084
54136.418114.3378
105036.744014.4661
155937.067014.5933
206837.387214.7194
257737.704714.8444
308638.019514.9683
359538.331815.0913
4010438.641515.2132

918 Hz Half Wavelength and Standing Waves

The half wavelength of a 918 Hz sound wave is 0.19 meters, 18.69 cm, 0.61 feet (0 feet and 7.36 inches) or 7.36 inches when travelling in air at 20°C (68°F).

Modes (or standing waves) will occur at 918 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 918 Hz wavelength = 0.37 meters, or 1.23 feet in air at 20°C (68°F).

918 Hz Standing Waves Distances

n Distance (m) Distance (ft)
10.190.61
20.371.23
30.561.84
40.752.45
50.933.07

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

Given the relatively small 918 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 918 Hz To ms

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

Because a 918 Hz wave will ocillate 918 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 = 918 Hz

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

1 / 918 Hz * 1000 = 1.09 ms.