51 Hz Wavelength

How Long Is a 51 Hz Wavelength?

A 51 Hz sound wave has a wavelength of 6.73 meters, 672.97 cm, 22.08 feet (22 feet and 0.95 inches) or 264.95 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 = 51 Hz
which gives a wavelength λ of 6.73 meters, or 22.08 feet.

51 Hz Wavelength Depending on Temperature

The speed of sound in air depends on temperature. Here is how the wavelenght of a 51 Hz sound wave will vary according to temperature:

Temp (°C) Temp (°F) 51 Hz wavelength (m)51 Hz wavelength (ft)
-40-406.001619.6903
-35-316.065619.9004
-30-226.129020.1082
-25-136.191720.3139
-20-46.253720.5175
-1556.315220.7191
-10146.376120.9188
-5236.436321.1166
0326.496121.3126
5416.555321.5068
10506.613921.6992
15596.672121.8900
20686.729722.0791
25776.786822.2666
30866.843522.4525
35956.899722.6369
401046.955522.8198

51 Hz Half Wavelength and Standing Waves

The half wavelength of a 51 Hz sound wave is 3.36 meters, 336.48 cm, 11.04 feet (11 feet and 0.47 inches) or 132.47 inches when travelling in air at 20°C (68°F).

Modes (or standing waves) will occur at 51 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 51 Hz wavelength = 6.73 meters, or 22.08 feet in air at 20°C (68°F).

51 Hz Standing Waves Distances

n Distance (m) Distance (ft)
13.3611.04
26.7322.08
310.0933.12
413.4644.16
516.8255.20

Given the relatively large 51 Hz half wavelength, standing waves will occur at that frequency in small listening rooms.

You can try to minimze the room modes at 51 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 51 Hz To ms

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

Because a 51 Hz wave will ocillate 51 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 = 51 Hz

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

1 / 51 Hz * 1000 = 19.61 ms.