4,140 Hz Wavelength

How Long Is a 4140 Hz Wavelength?

A 4140 Hz sound wave has a wavelength of 0.08 meters, 8.29 cm, 0.27 feet (0 feet and 3.26 inches) or 3.26 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 = 4140 Hz
which gives a wavelength λ of 0.08 meters, or 0.27 feet.

4140 Hz Wavelength Depending on Temperature

The speed of sound in air depends on temperature. Here is how the wavelenght of a 4140 Hz sound wave will vary according to temperature:

Temp (°C) Temp (°F) 4140 Hz wavelength (cm)4140 Hz wavelength (in)
-40-407.39332.9107
-35-317.47222.9418
-30-227.55022.9725
-25-137.62743.0029
-20-47.70393.0330
-1557.77963.0628
-10147.85463.0923
-5237.92883.1216
0328.00243.1506
5418.07533.1793
10508.14763.2077
15598.21923.2359
20688.29023.2639
25778.36063.2916
30868.43043.3191
35958.49973.3463
401048.56833.3734

4140 Hz Half Wavelength and Standing Waves

The half wavelength of a 4140 Hz sound wave is 0.04 meters, 4.15 cm, 0.14 feet (0 feet and 1.63 inches) or 1.63 inches when travelling in air at 20°C (68°F).

Modes (or standing waves) will occur at 4140 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 4140 Hz wavelength = 0.08 meters, or 0.27 feet in air at 20°C (68°F).

4140 Hz Standing Waves Distances

n Distance (m) Distance (ft)
10.040.14
20.080.27
30.120.41
40.170.54
50.210.68

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

Given the relatively small 4140 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 4140 Hz To ms

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

Because a 4140 Hz wave will ocillate 4140 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 = 4140 Hz

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

1 / 4140 Hz * 1000 = 0.24 ms.