66 Hz Wavelength

How Long Is a 66 Hz Wavelength?

A 66 Hz sound wave has a wavelength of 5.2 meters, 520.02 cm, 17.06 feet (17 feet and 0.73 inches) or 204.73 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 = 66 Hz
which gives a wavelength λ of 5.2 meters, or 17.06 feet.

66 Hz Wavelength Depending on Temperature

The speed of sound in air depends on temperature. Here is how the wavelenght of a 66 Hz sound wave will vary according to temperature:

Temp (°C) Temp (°F) 66 Hz wavelength (m)66 Hz wavelength (ft)
-40-404.637615.2153
-35-314.687115.3776
-30-224.736015.5381
-25-134.784515.6971
-20-44.832415.8544
-1554.879916.0102
-10144.927016.1646
-5234.973516.3174
0325.019716.4688
5415.065416.6189
10505.110816.7676
15595.155716.9150
20685.200217.0611
25775.244417.2060
30865.288217.3497
35955.331617.4921
401045.374717.6335

66 Hz Half Wavelength and Standing Waves

The half wavelength of a 66 Hz sound wave is 2.6 meters, 260.01 cm, 8.53 feet (8 feet and 6.37 inches) or 102.37 inches when travelling in air at 20°C (68°F).

Modes (or standing waves) will occur at 66 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 66 Hz wavelength = 5.2 meters, or 17.06 feet in air at 20°C (68°F).

66 Hz Standing Waves Distances

n Distance (m) Distance (ft)
12.608.53
25.2017.06
37.8025.59
410.4034.12
513.0042.65
615.6051.18

Given the relatively large 66 Hz half wavelength, standing waves will occur at that frequency in small listening rooms.

You can try to minimze the room modes at 66 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 66 Hz To ms

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

Because a 66 Hz wave will ocillate 66 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 = 66 Hz

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

1 / 66 Hz * 1000 = 15.15 ms.