913 Hz Wavelength

How Long Is a 913 Hz Wavelength?

A 913 Hz sound wave has a wavelength of 0.38 meters, 37.59 cm, 1.23 feet (1 feet and 2.8 inches) or 14.8 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 = 913 Hz
which gives a wavelength λ of 0.38 meters, or 1.23 feet.

913 Hz Wavelength Depending on Temperature

The speed of sound in air depends on temperature. Here is how the wavelenght of a 913 Hz sound wave will vary according to temperature:

Temp (°C) Temp (°F) 913 Hz wavelength (cm)913 Hz wavelength (in)
-40-4033.524913.1988
-35-3133.882513.3396
-30-2234.236313.4789
-25-1334.586513.6168
-20-434.933313.7532
-15535.276613.8884
-101435.616514.0223
-52335.953314.1548
03236.287014.2862
54136.617614.4164
105036.945214.5454
155937.270014.6732
206837.592014.8000
257737.911214.9257
308638.227815.0503
359538.541715.1739
4010438.853215.2965

913 Hz Half Wavelength and Standing Waves

The half wavelength of a 913 Hz sound wave is 0.19 meters, 18.8 cm, 0.62 feet (0 feet and 7.4 inches) or 7.4 inches when travelling in air at 20°C (68°F).

Modes (or standing waves) will occur at 913 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 913 Hz wavelength = 0.38 meters, or 1.23 feet in air at 20°C (68°F).

913 Hz Standing Waves Distances

n Distance (m) Distance (ft)
10.190.62
20.381.23
30.561.85
40.752.47
50.943.08

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

Given the relatively small 913 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 913 Hz To ms

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

Because a 913 Hz wave will ocillate 913 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 = 913 Hz

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

1 / 913 Hz * 1000 = 1.1 ms.