What is white noise?

What is White Noise?

What is White Noise?

Most people might think that white noise is just a hissing noise or simply static and in a way they would be right. White noise however, has distinct parameters and most notably it is a band of random, but audible sound frequencies in the range of 20 to 20,000 Hz.

So white noise is in fact a misnomer, because it is actually a random collection of sounds within the audible range. It has been compared to white light, because just as white light contains the entire spectrum of light colors in the visible range, white noise contains the entire spectrum of frequencies in the audible range.    

Creating white noise sound

You can generate white noise on a sound synthesizer and sound designers have been using white noise to create a myriad of sounds, such as the crashing of surf or the rustling of the wind.

Sound engineers also use white noise to analyze the resonant frequencies in concert halls, so that during a concert they can mask these resonant frequencies and stop them from interfering with the acoustic quality of the musical performance.

One of the issues with white noise is that it is difficult to eliminate completely. So for example if an audio recording contains a hissing noise, engineers can use a spectral analysis to identify the frequencies of the noise and compensate for these using an equalizer.

The problem is that by definition, white noise covers the entire range of audible frequencies, so it is for this reason that it can be difficult to eliminate completely.

Different types of white noise sounds

There are lots of reasons why people use white noise machines and here are just a few of them:

  • Relaxation.
  • Help with insomnia, disturbed sleep patterns and restlessness at night.
  • To calm a fussy baby and help them to settle and sleep.
  • Tune out the snoring of their partner.
  • Focus and concentrate while at work or studying.
  • Mask noisy neighbors.
  • Help shift workers to sleep during the day.
  • To prevent eavesdropping in clinical situations.
  • Reduce the problems of tinnitus and ringing in the ears.
  • Sooth or calm pets, suffering from separation anxiety or too much exuberance.
  • Helps to calm people with ADHD.

White noise for sleeping

Woman using a white noise machine to sleepSome people can only have a good night’s sleep if they hear the noise of a fan on in their bedroom, the radio playing low or even the TV left on.

All of these act in a similar way to a noise cancelling machine, in that they mask or mute sounds which may wake you from a deep sleep.

For some people, actually falling asleep is more of a problem than being woken from a deep sleep, and in these cases, a white noise fan can quite often relax them enough, so that they fall asleep with no problem.

White noise for studying

white noise for studyingResearch is still out on whether white noise actually helps people to focus more when they are studying.

There is evidence that it is of benefit in ADHD sufferers and in older adults to help them with memory loss.

Many people however, swear that ambient white noise helps them to focus and concentrate more easily when they are studying.

Whether white noise is of any real benefit in studying might depend on personal preferences –whether you like to study to music or prefer peace and quiet, as well as whether or not you need to mask annoying noises in your environment.

White noise at work

white noise in the workplaceMany people use a white noise machine at work, particularly in open plan offices to help them to focus on their work.

They find that the chitter chatter of work mates or even the total silence of an excessively quiet work environment can hinder their productivity and a noise cancelling machine works really well for them. They even buy two, so they can have one at work and one at home!


 Overcoming jet lag with white noise

jet lag recoveryOne of the huge problems in dealing with jet lag is the problem it causes in your sleeping patterns.

Some people can take a week or more to return to a normal sleeping routine and actually feel alive again, instead of half dead.

There are many jet lag solutions around, but one of the most successful involves using white noise sounds to mask any background noises, helping you to fall asleep at the right time.

One machine in particular, the Sound Oasis white noise machine, has a unique sound track specifically formulated for fast jet lag recovery.

What is pink noise?

Pink noise has more power or energy at the lower end of the frequency range, than at the higher ranges and so comes across as a gentler and much deeper sound than white noise.

Pink noise appeals to people who find that white noise is too harsh or tinny and is not conducive to relaxation for them.

Pink noise is used to mask low frequency, background noises and is quite often used in offices and other work environments to help raise productivity levels.

What is brown noise?

Brown noise is also known as red noise, is similar to pink noise, but is deeper, and really removes all of the hisses and tininess of white noise.

So in other words, brown noise is the lower end of the audible frequency range and has a softer, deeper quality than either white or pink noise – it is similar to heavy rainfall or a deep humming sound.

What is gray noise?

Gray noise is a random noise that has the perception of equal loudness at all frequencies. It has more power at the top and bottom of the frequency spectrum, which complements the acoustics of the human ear, so that to the listener all of the frequencies sound equally loud.

Examples of white noise machines


Sleep Easy White noise machine

Sleep Easy Sound Conditioner

The Sleep Easy Sound Conditioner is a very affordable background noise generator, which is simple to use and very effective at helping you drift off to an undisturbed night’s sleep.

Marpac DOHM

Marpac DOHM-DS

The Marpac is the official white noise machine of the Sleep Foundation, producing a gentle and consistent background noise of rushing air, masking any unwanted noises. 

LectroFan white noise machine


With the LectroFan you can chose between a white noise setting and the sound of a white noise fan, which some people prefer. You also have 10 different settings for each of these selections, so you can find just the right tone and volume. 

Concluding thoughts

If you just want an ambient noise generator, then a white noise machine will most probably fit the bill. On the other hand, if you want to play tinkling waterfalls, ocean waves or gentle rainfall to help you fall asleep then you want a sound machine rather than a white noise machine.

Some sleep machines will play both white noise and natural sounds, but some will only play one or the other. Whichever you decide on purchasing, you can be sure that from now on you can look forward to an uninterrupted night’s sleep.