997 Hz Wavelength

How Long Is a 997 Hz Wavelength?

A 997 Hz sound wave has a wavelength of 0.34 meters, 34.42 cm, 1.13 feet (1 feet and 1.55 inches) or 13.55 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 = 997 Hz
which gives a wavelength λ of 0.34 meters, or 1.13 feet.

997 Hz Wavelength Depending on Temperature

The speed of sound in air depends on temperature. Here is how the wavelenght of a 997 Hz sound wave will vary according to temperature:

Temp (°C) Temp (°F) 997 Hz wavelength (cm)997 Hz wavelength (in)
-40-4030.700412.0868
-35-3131.027812.2157
-30-2231.351812.3432
-25-1331.672512.4695
-20-431.990012.5945
-15532.304412.7183
-101432.615712.8408
-52332.924212.9623
03233.229713.0826
54133.532413.2018
105033.832513.3199
155934.129913.4370
206834.424713.5530
257734.717113.6681
308635.007013.7823
359535.294513.8955
4010435.579714.0077

997 Hz Half Wavelength and Standing Waves

The half wavelength of a 997 Hz sound wave is 0.17 meters, 17.21 cm, 0.56 feet (0 feet and 6.78 inches) or 6.78 inches when travelling in air at 20°C (68°F).

Modes (or standing waves) will occur at 997 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 997 Hz wavelength = 0.34 meters, or 1.13 feet in air at 20°C (68°F).

997 Hz Standing Waves Distances

n Distance (m) Distance (ft)
10.170.56
20.341.13
30.521.69
40.692.26
50.862.82

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

Given the relatively small 997 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 997 Hz To ms

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

Because a 997 Hz wave will ocillate 997 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 = 997 Hz

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

1 / 997 Hz * 1000 = 1 ms.