Masking Binaural Beats

I always say ask me anything and a lot of people are doing just that lately and today I thought I would talk about masking binaural beats with noise

Inbox: What is masking?

There are a lot of binaural beats in the world. There are so many, in fact, that many online music stores like Apple Music have found subtle ways to ban them. (Apple, for example, black-listed the word “binaural” and the phrase “binaural beats” from use in titles and descriptions of new music submissions in 2018 or so.) And it’s easy to see why the ban exists: binaural beats alone make for a crap listening experience. Here’s some proof:

One minute of a 4Hz Delta binaural beat via 100Hz, 300Hz and 500Hz carrier frequencies.

While this tone set is deliberately uninspiring, by literally any definition binaural beats alone do not meet the minimum criteria to be classified as music and therefor do not belong in a music store. (Apps, on the hand, are an altogether different situation about which I know nothing.)

There is also the issue of listening fatigue. While not clinically recognized, listening fatigue is a phenomenon that occurs after prolonged exposure to an auditory stimulus. When listening only to binaural beats, the continued exposure to high levels of audio in such a narrow bandwidth can lead to tiredness, discomfort, irritability, headaches and even pain and hearing loss. To avoid this fatigue, binaural beats need to be masked.

Initially, Monroe’s solution to this problem was to mask the sound with noise. Masking occurs when the perception of one sound is affected by the presence of another sound. By adding noise, the carrier frequencies for the binaural beats are less likely to cause fatigue because the the sound energy of white noise is equally–but randomly–spread across the entire frequency spectrum.

In physics and audio engineering, noise is described using colors. Brown noise, for example, decreases in power as the frequency rises. The perception of brown noise, then, is that of the low roar of a waterfall: it is deeper and warmer sounding than white noise. And it was Robert Monroe’s choice for Hemi-Sync®.

One minute of a 4Hz Delta binaural beat via 100Hz, 300Hz and 500Hz carrier frequencies with a modulating pink noise (because I don’t have a brown noise generator and I’m too tired deal with that right now…)

Using music to mask binaural beats and Hemi-Sync® is pretty self evident and in the late eighties and early nineties, Hemi-Sync® launched a line of products called Metamusic®. Initially a simple experiment using music created in house, folks at the Monroe Institute began reaching out to artists to create the Metamusic® Artist Series, a collection of more fully realized productions. Higher was maybe the fourth or fifth release in the Metamusic® Artist Series.

For better or for worse, this introduced its own set of unique problems.