123 Hz Wavelength

How Long Is a 123 Hz Wavelength?

A 123 Hz sound wave has a wavelength of 2.79 meters, 279.04 cm, 9.15 feet (9 feet and 1.86 inches) or 109.86 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 = 123 Hz
which gives a wavelength λ of 2.79 meters, or 9.15 feet.

123 Hz Wavelength Depending on Temperature

The speed of sound in air depends on temperature. Here is how the wavelenght of a 123 Hz sound wave will vary according to temperature:

Temp (°C) Temp (°F) 123 Hz wavelength (m)123 Hz wavelength (ft)
-40-402.48858.1643
-35-312.51508.2514
-30-222.54138.3375
-25-132.56738.4228
-20-42.59308.5073
-1552.61858.5909
-10142.64378.6737
-5232.66878.7557
0322.69358.8369
5412.71808.9174
10502.74248.9972
15592.76659.0763
20682.79049.1547
25772.81419.2325
30862.83769.3096
35952.86099.3860
401042.88409.4619

123 Hz Half Wavelength and Standing Waves

The half wavelength of a 123 Hz sound wave is 1.4 meters, 139.52 cm, 4.58 feet (4 feet and 6.93 inches) or 54.93 inches when travelling in air at 20°C (68°F).

Modes (or standing waves) will occur at 123 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 123 Hz wavelength = 2.79 meters, or 9.15 feet in air at 20°C (68°F).

123 Hz Standing Waves Distances

n Distance (m) Distance (ft)
11.404.58
22.799.15
34.1913.73
45.5818.31
56.9822.89
68.3727.46
79.7732.04
811.1636.62
912.5641.20
1013.9545.77
1115.3550.35

Given the relatively large 123 Hz half wavelength, standing waves will occur at that frequency in small listening rooms.

You can try to minimze the room modes at 123 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 123 Hz To ms

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

Because a 123 Hz wave will ocillate 123 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 = 123 Hz

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

1 / 123 Hz * 1000 = 8.13 ms.