6,420 Hz Wavelength

How Long Is a 6420 Hz Wavelength?

A 6420 Hz sound wave has a wavelength of 0.05 meters, 5.35 cm, 0.18 feet (0 feet and 2.1 inches) or 2.1 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 = 6420 Hz
which gives a wavelength λ of 0.05 meters, or 0.18 feet.

6420 Hz Wavelength Depending on Temperature

The speed of sound in air depends on temperature. Here is how the wavelenght of a 6420 Hz sound wave will vary according to temperature:

Temp (°C) Temp (°F) 6420 Hz wavelength (cm)6420 Hz wavelength (in)
-40-404.76761.8770
-35-314.81851.8970
-30-224.86881.9169
-25-134.91861.9365
-20-44.96791.9559
-1555.01671.9751
-10145.06511.9941
-5235.11302.0130
0325.16042.0317
5415.20752.0502
10505.25402.0685
15595.30022.0867
20685.34602.1047
25775.39142.1226
30865.43642.1403
35955.48112.1579
401045.52542.1753

6420 Hz Half Wavelength and Standing Waves

The half wavelength of a 6420 Hz sound wave is 0.03 meters, 2.67 cm, 0.09 feet (0 feet and 1.05 inches) or 1.05 inches when travelling in air at 20°C (68°F).

Modes (or standing waves) will occur at 6420 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 6420 Hz wavelength = 0.05 meters, or 0.18 feet in air at 20°C (68°F).

6420 Hz Standing Waves Distances

n Distance (m) Distance (ft)
10.030.09
20.050.18
30.080.26
40.110.35
50.130.44

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

Given the relatively small 6420 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 6420 Hz To ms

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

Because a 6420 Hz wave will ocillate 6420 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 = 6420 Hz

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

1 / 6420 Hz * 1000 = 0.16 ms.