764 Hz Wavelength

How Long Is a 764 Hz Wavelength?

A 764 Hz sound wave has a wavelength of 0.45 meters, 44.92 cm, 1.47 feet (1 feet and 5.69 inches) or 17.69 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 = 764 Hz
which gives a wavelength λ of 0.45 meters, or 1.47 feet.

764 Hz Wavelength Depending on Temperature

The speed of sound in air depends on temperature. Here is how the wavelenght of a 764 Hz sound wave will vary according to temperature:

Temp (°C) Temp (°F) 764 Hz wavelength (cm)764 Hz wavelength (in)
-40-4040.063215.7729
-35-3140.490515.9411
-30-2240.913316.1076
-25-1341.331816.2724
-20-441.746216.4355
-15542.156416.5970
-101442.562716.7570
-52342.965216.9154
03243.363917.0724
54143.759017.2279
105044.150517.3821
155944.538617.5349
206844.923417.6864
257745.304917.8366
308645.683217.9855
359546.058418.1332
4010446.430518.2797

764 Hz Half Wavelength and Standing Waves

The half wavelength of a 764 Hz sound wave is 0.22 meters, 22.46 cm, 0.74 feet (0 feet and 8.84 inches) or 8.84 inches when travelling in air at 20°C (68°F).

Modes (or standing waves) will occur at 764 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 764 Hz wavelength = 0.45 meters, or 1.47 feet in air at 20°C (68°F).

764 Hz Standing Waves Distances

n Distance (m) Distance (ft)
10.220.74
20.451.47
30.672.21
40.902.95
51.123.68

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

Given the relatively small 764 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 764 Hz To ms

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

Because a 764 Hz wave will ocillate 764 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 = 764 Hz

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

1 / 764 Hz * 1000 = 1.31 ms.