281 Hz Wavelength

How Long Is a 281 Hz Wavelength?

A 281 Hz sound wave has a wavelength of 1.22 meters, 122.14 cm, 4.01 feet (4 feet and 0.09 inches) or 48.09 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 = 281 Hz
which gives a wavelength λ of 1.22 meters, or 4.01 feet.

281 Hz Wavelength Depending on Temperature

The speed of sound in air depends on temperature. Here is how the wavelenght of a 281 Hz sound wave will vary according to temperature:

Temp (°C) Temp (°F) 281 Hz wavelength (m)281 Hz wavelength (ft)
-40-401.08933.5737
-35-311.10093.6118
-30-221.11243.6495
-25-131.12383.6869
-20-41.13503.7238
-1551.14623.7604
-10141.15723.7967
-5231.16823.8326
0321.17903.8681
5411.18973.9034
10501.20043.9383
15591.21093.9729
20681.22144.0072
25771.23184.0413
30861.24214.0750
35951.25234.1085
401041.26244.1417

281 Hz Half Wavelength and Standing Waves

The half wavelength of a 281 Hz sound wave is 0.61 meters, 61.07 cm, 2 feet (2 feet and 0.04 inches) or 24.04 inches when travelling in air at 20°C (68°F).

Modes (or standing waves) will occur at 281 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 281 Hz wavelength = 1.22 meters, or 4.01 feet in air at 20°C (68°F).

281 Hz Standing Waves Distances

n Distance (m) Distance (ft)
10.612.00
21.224.01
31.836.01
42.448.01
53.0510.02
63.6612.02
74.2714.03
84.8916.03
95.5018.03
106.1120.04
116.7222.04
127.3324.04
137.9426.05
148.5528.05
159.1630.05
169.7732.06
1710.3834.06
1810.9936.07
1911.6038.07
2012.2140.07
2112.8242.08
2213.4444.08
2314.0546.08
2414.6648.09
2515.2750.09

Given the relatively large 281 Hz half wavelength, standing waves will occur at that frequency in small listening rooms.

You can try to minimze the room modes at 281 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 281 Hz To ms

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

Because a 281 Hz wave will ocillate 281 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 = 281 Hz

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

1 / 281 Hz * 1000 = 3.56 ms.