A white noise machine may be used for a variety of purposes. Depending on the use for which it is planned, the noise produced may be more “pink” than white. The colors are used to refer to the frequency of the sounds emitted. There is actually no visible color associated with the sounds.
Most manufacturers refer to them as white noise machines even if the sounds produced are not of the flat equal frequency that is technically considered “white”. If it is actually a white noise generator it will cut through background noises, which is an attractive feature for the sirens used on emergency vehicles.
Musicians use the sounds to set up equalizers and PA systems. They are used to test amplifiers, microphones and electronic filters. There are also medicinal applications.
In the condition known as tinnitus, patients suffer from a constant ringing in their ears, but examination shows no physical deformity of the ear that would cause such a ringing. The ringing often interferes with a person’s ability to fall asleep. So, doctors often suggest a white noise machine to mask the sound.
A similar device has been developed that fits into the ear of a tinnitus sufferer. These are professionally fitted, similar to the way hearing aids are fitted, and the sounds emitted by the devices are tuned to the individual. When the technician finds a sound that masks the ringing in the patient’s ears, the frequency is noted and that is the sound that will be emitted. So, truly, they are not white noise machines, but they are based on the same idea.
Masking other noises or creating privacy is one of the best-known purposes of the generators. They may be used in a doctor’s or psychiatrist’s waiting room to provide a comfortable feeling and to ensure the patient’s privacy. The sounds emitted are different from what people think of as elevator music, which can become annoying.
Eventually, if the volume of a white noise generator is gradually increased, a person working in the office will stop noticing the sound. They block it out.
One of the most popular applications for white noise machines is for people that have difficulty sleeping. In addition to masking other sounds, the constant noises help to prevent people from waking due to noises in a quiet room.
Although most people sleep best when it is quiet, our ears begin to detect the tiniest noises when it is very quiet. So, the cracking that occurs when a house settles or an air conditioning unit kicking off or on could cause a light sleeper to wake up and sometimes they have difficulty falling asleep again.
When there are constant noises at a low volume and a low frequency, light sleepers are less likely to wake up. Most users feel that the devices work well for that purpose.
In addition to emitting random sounds, the white noise machines available today often include the sound of waves or rushing water. Falling rain is another common choice. Soft music may also be included on the soundtrack. Most manufacturers recommend that users start with the volume on the lowest possible setting and then increase it gradually, just as an office worker would do.
A white noise generator can also be used to mask street noises and other sounds from outside. Even someone that is not a very light sleeper could have difficulty dozing off when city life is close around them.
The cost of the devices varies. Some clock radios are equipped with random sound generators. Soundtracks can also be downloaded and played on the speakers of a PC or laptop.
Basically, a white noise machine could improve your sleep at home and your productivity in the office by reducing distractions. In other words, it could be a "sound investment".