50 Hz Wavelength

How Long Is a 50 Hz Wavelength?

A 50 Hz sound wave has a wavelength of 6.86 meters, 686.43 cm, 22.52 feet (22 feet and 6.25 inches) or 270.25 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 = 50 Hz
which gives a wavelength λ of 6.86 meters, or 22.52 feet.

50 Hz Wavelength Depending on Temperature

The speed of sound in air depends on temperature. Here is how the wavelenght of a 50 Hz sound wave will vary according to temperature:

Temp (°C) Temp (°F) 50 Hz wavelength (m)50 Hz wavelength (ft)
-40-406.121720.0842
-35-316.186920.2984
-30-226.251620.5103
-25-136.315520.7202
-20-46.378820.9279
-1556.441521.1335
-10146.503621.3372
-5236.565121.5390
0326.626021.7388
5416.686421.9369
10506.746222.1332
15596.805522.3278
20686.864322.5206
25776.922622.7119
30866.980422.9015
35957.037723.0896
401047.094623.2762

50 Hz Half Wavelength and Standing Waves

The half wavelength of a 50 Hz sound wave is 3.43 meters, 343.21 cm, 11.26 feet (11 feet and 3.12 inches) or 135.12 inches when travelling in air at 20°C (68°F).

Modes (or standing waves) will occur at 50 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 50 Hz wavelength = 6.86 meters, or 22.52 feet in air at 20°C (68°F).

50 Hz Standing Waves Distances

n Distance (m) Distance (ft)
13.4311.26
26.8622.52
310.3033.78
413.7345.04
517.1656.30

Given the relatively large 50 Hz half wavelength, standing waves will occur at that frequency in small listening rooms.

You can try to minimze the room modes at 50 Hz by trying different speaker positions, listening positions or by placing bass traps. These can absorb frequencies as low as 63 Hz.

How To Convert 50 Hz To ms

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

Because a 50 Hz wave will ocillate 50 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 = 50 Hz

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

1 / 50 Hz * 1000 = 20 ms.