White Noise and Pink Noise Article

White and Pink Noise are simply two types of generated acoustic noise.  Although noise is used for a variety of purposes; it is usually used to mask distracting sounds in a pleasing way.  Many people describe white noise as similar to running water, or rain; or similar to the noise on a vacant TV channel.  When the noise volume is modulated, it can sound very similar to ocean waves.  In some cases White or Pink Noise is mixed with other sounds to create plesant masking programs (i.e. Thunder, Fountains, or Fan Noise).

The term white noise is intended to be analogous to white light.  Since white light contains all light frequencies in equal proportions; white noise is intended to be similar in that it contains all sound frequencies (in the range of human hearing).  Usually this is accomplished by generating random frequencies in equal proportions per octave either using a computer, special electronics, or a dedicated synthesizer.  Since every increasing octave is double the size of the previous, this effectively increases the high frequency content.

Pink noise is basically White noise, but with the amplitude decreasing with increasing frequency at a constant rate per octave (3db).  Most simply put, the lower frequencies are emphasized as a result (compared to white noise).  You will find that they sound similar; but most can notice that the Pink Noise has an emphasized low end.  White noise is the more popular and well known of the two.

An advantage of Pink noise is the added low frequency emphasis.  This makes it less like static/rain and more like a distant ocean roar.  This extra low frequency emphasis can be a benefit for those dealing with low frequency noises.  if you have to deal with car sub woofers or industrial noises in your neighborhood or work place, this added low end emphasis can provide additional masking power.  Keep in mind this can help mask lower frequency noise, but it will not mask the mechanical vibrations usually associated with very low frequency sounds or very loud noises.  Generally, you will still feel these noises as mechanical vibrations and their artifacts.  If you are dealing with noises of this magnitude you might want to consider sound proofing your environment if pink noise is not enough.  Typically this is fairly expensive because stopping mechanical vibrations requires adding mass or isolating an environment.
 

White and Pink noise have been used in sound synthesis for many years.  If you have played with a synthesizer, there is a good chance you've heard the terms and sounds.  Most synthesizers include dedicated white and pink noise circuits, which are used for a variety of important purposes.  Typically, they are popular for designing rain, wind, water, buzzes, drums, gun shots, explosions and more; as used for special effects for movies and video games.

Since noise can mask unpleasant background noises, and can sound like a pleasant rain fall; some people find it useful to help fall asleep, nap, or relax with.  We've seen some very broad claims made about the benefits of white and pink noise.  Most of which we consider personal and fairly subjective (to each his own).  In any case, it would seem to follow that effectively masking sudden or continuous background noises would be beneficial for sleeping, relaxing, concentration, meditation, and studying.  Obviously, all of these activities are better served in a distraction free environment.

All of this has generated a large market for noise machines and devices (sleep machines - sound conditioners - etc).  These machines typically generate white noise and modulate it to synthesize various sounds.  Sometimes sold specifically as sleep machines, the intention is to mask noise and generate sounds that help relax and lull you to sleep.  Since these are just generating noise, they are not fundamentally different from simply playing a CD.  However, since many typically play the noise through one tiny little speaker, the quality can be limited; and a good machine can be expensive.  If you already have a quality CD player or an audio playback system, our noise CDs or downloads are a very inexpensive way to go.
 

If you are considering buying a noise machine, you should consider buying a noise CD, try a sampler CD, or try a MP3 noise download.  This will save you money, and utilize your existing resources (your CD player or Computer/CDR).  Another nice thing about CDs is that they are portable and compact; so it's easy to take them wherever you go.  Since machine based systems are typically hardware based, they normally can not be upgraded to utilize new noises.  However, by using CDs or MP3s, one simply can purchase a new title (we carry several noise "flavors") or even simply download and burn a personal CD for instant gratification; usually at a significant savings.   You can also simply loop them (repeat function in software or on CD/MP3 player) to create any duration of noise necessary.  With our noise downloads you are allowed to burn one copy to CDR for personal use and backup.

Some people ask how to find the best White or Pink noise?  White or Pink noise from quality manufacturers should sound very similar under strict circumstances.  Personal preferences, the quality of the recording, stereo vs. mono, mastering technique, synthesis techniques, playback system; will all affect the final result.  So, while while there are several factors to consider; it's also very subjective and some depends on your playback system quality, and hearing abilities.  If you have a low quality playback system, then it's unlikely you will notice the subtle differences among high quality manufacturers; but we recommend you get the best quality for use on other playback systems or a future upgrade.

We generate our noise using either an analog synthesizer circuit or a modern computer hardware based synthesizer (we sell both "Digital" & "Analog" sources for variety); and then digitally record, master at maximum level, and duplicate our noise CDRs.  All CDs are then tested during packaging. This way, you will get a high quality recording that is as close to the original sound quality as possible.  All of our CDs are stereo (two distinct tracks) noise.  We don't delay a channel or alter the phase to generate a psudo-stereo sound field, it's simply two tracks of noise to maintain the original integrity.  We also digitally print our full color CD title graphics and text directly onto the CDR using special hardware; we don't just glue cheap paper labels on our titles.  All CDs are simply packaged in an inexpensive CD jewel case allowing us to sell our quality titles for less than most.