984 Hz Wavelength

How Long Is a 984 Hz Wavelength?

A 984 Hz sound wave has a wavelength of 0.35 meters, 34.88 cm, 1.14 feet (1 feet and 1.73 inches) or 13.73 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 = 984 Hz
which gives a wavelength λ of 0.35 meters, or 1.14 feet.

984 Hz Wavelength Depending on Temperature

The speed of sound in air depends on temperature. Here is how the wavelenght of a 984 Hz sound wave will vary according to temperature:

Temp (°C) Temp (°F) 984 Hz wavelength (cm)984 Hz wavelength (in)
-40-4031.105912.2464
-35-3131.437712.3771
-30-2231.766012.5063
-25-1332.091012.6342
-20-432.412712.7609
-15532.731212.8863
-101433.046613.0105
-52333.359113.1335
03233.668713.2554
54133.975513.3762
105034.279513.4959
155934.580813.6145
206834.879513.7321
257735.175713.8487
308635.469513.9644
359535.760814.0790
4010436.049714.1928

984 Hz Half Wavelength and Standing Waves

The half wavelength of a 984 Hz sound wave is 0.17 meters, 17.44 cm, 0.57 feet (0 feet and 6.87 inches) or 6.87 inches when travelling in air at 20°C (68°F).

Modes (or standing waves) will occur at 984 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 984 Hz wavelength = 0.35 meters, or 1.14 feet in air at 20°C (68°F).

984 Hz Standing Waves Distances

n Distance (m) Distance (ft)
10.170.57
20.351.14
30.521.72
40.702.29
50.872.86

We typically don't treat rooms for standing waves above 300 Hz.

Given the relatively small 984 Hz half wavelength, you can treat your room by using thick acoustic foam. This will absorb frequencies as low as 250 Hz, and all the way up to 20,000 Hz.

How To Convert 984 Hz To ms

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

Because a 984 Hz wave will ocillate 984 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 = 984 Hz

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

1 / 984 Hz * 1000 = 1.02 ms.