Low Frequency White Noise
Both white and pink noise are considered broadband noises. Both of them are made of all frequencies that are audible to humans, so all frequencies anywhere between 20 and 20000 hertz. But the way their signal power is distributed among all frequencies radically differs, and you can see that using a power analyzer or just by looking at the simple sound spectrum graphs provided below.
Low Frequency White Noise
Therefore, at lower frequencies, the octave bands are narrower, and at higher frequencies, the octave bands are wider. To help you grasp this concept better, the table below shows the typical octave bands used in acoustics and the frequency range contained in each band. The numbers make it very clear: the 8000 hz octave band regroups a lot more frequencies than the 63 Hz octave band.
Now remember earlier in figure 1 how the white noise spectrum looked like a flat straight line when viewed in narrow bands on a linear scale? Based on what you know about pink noise, and how its energy distribution differs from white noise, how would you expect its spectrum to look like when viewed in narrow bands instead of third-octaves?
Keeping in mind what you know about octaves and how they work: if white noise has equal power per hertz throughout all frequencies and shows a positive slope when viewed in octave mode, then pink noise, which has equal power per octave throughout all frequencies, will logically show a negative slope when viewed in narrow bands, right? And there you go:
Graphically speaking, sound masking is practically the total opposite of white noise. Indeed, as we go from lower to higher frequencies, the white noise signal gains 3 decibels per octave while the typical sound masking signal loses 3 decibels per octave. Furthermore, unlike white noise, sound masking is everything but a straight, rather bumpy slope. In the figure below, notice how the sound masking spectrum gently curves down, almost without any noticeable increment?
We at Yogasleep have a confession to make. The Dohm is not actually a white noise machine. What?! Yes, it's true. The Yogasleep Dohm produces, not white noise, but pink noise. Well, you might be wondering, what's the difference? We're glad you asked.
White noise refers to a type of sound that's an equal intensity across all frequencies audible by the human ear; similar to white light, which contains all visible light at equal intensity. White noise is produced by randomly generating noise across the entire sound spectrum, and it ends up sounding like radio static, which some people enjoy as background noise, while others find it irritating.
This is the major difference between pink and white noise. In white noise, the power is constant, but in pink noise, as the numbers get bigger, the difference in power becomes smaller, so the higher-pitched sounds are softer.
Because the lower frequencies are louder than the higher frequencies in pink noise, it sounds less abrasive and leads to a better night's sleep. Less like radio static, and more like leaves rustling.
Pink noise has been found by many studies to be the most soothing background sound. Not only that, but studies have also shown that going to sleep listening to pink noise from a sound machine helps improve memory the next day and could have long-lasting positive effects on memory and concentration.
It can be seemingly hard to find readily available sources of pink noise. Luckily, the Yogasleep Go, Yogasleep Nod, a