Psychoacoustics and the science of relaxation music

By Christopher Lloyd Clarke

Psy•cho•acous•tics / adjective:
A branch of science dealing with the perception of hearing and sensations produced by sound.

As a composer, whenever I create royalty free meditation music or hypnosis music I always take the principles of psychoacoustics into account. Essentially, psychoacoustics is the study of the perception of sound, and the ways in which it affects you mentally, emotionally and even physically. You could think of it as a form of music psychology.
The fundamental reason why we enjoy listening to music is because it is mood altering. Music can stimulate or sooth you. It can relieve stress and it can induce stress. It can elevate you or depress you.
Music can be extremely powerful in this regard. Have you ever been so touched by a beautiful piece of music that you cried? Have you ever cringed at the sound of fingernails being dragged down a chalkboard? Most people answer “yes” to both of these questions.
So if sound can have such a strong effect on us, then how can we use this to our advantage? What can the study of psychoacoustics teach us about creating music that encourages altered states of consciousness, such as those we experience in meditation and hypnosis?
Some types of relaxation music are certainly more powerful than others. Some sounds are particularly hypnotic, some can cause trance - like states and some types of music, like those containing binaural beats, can even be used to alter the frequency of your brainwave activity, thereby helping to induce specific states of relaxation.
Let's get to know what some of these sounds are and how they are used to create music for deep meditation...


Sonic Mantras

“Sonic mantras” are the name that I give to repetitive musical sounds. These sounds can be used in place of a traditional meditation mantra. Provided that they are tonally pleasing and played at a slow tempo, repetitive sounds can be wonderfully relaxing.

Listening to Sonic Mantras tends to encourage feelings of safety and a state of relaxed focus. They can also help some people to let go of their conscious mind and drop into a trance state quite quickly. Unlike a traditional meditation mantra, Sonic Mantras will never lose their concentration or start thinking about whether or not they left the iron on this morning. They are predictable, reliable and, like the hypnotists swinging pendulum, quite soporific.

Music that contains Sonic Mantras is what I sometimes call “true” meditation music, because it embraces the time-honoured technique of using mantras to induce a state of meditation.

A Sonic Mantra can be comprised either of a single discrete sound or a series of repeating notes (in traditional music, this is referred to as an "ostinato"). Sonic Mantras can be very relaxing when played "naked", but in most cases I dress the Mantra in other instrumentation to create a more interesting and emotive musical performance.

Here are some great examples of music from our royalty free meditation music collection that contains these kinds of repetitive, trance inducing sounds.

Deep Within
The Essence of Peace
The Journey (Track 2 from the album "Vision Quest")



The word “drone” may sound a bit dull and uninspiring to you, but drone sounds can be very relaxing and are most suitable for deep meditation music. A classic example of a drone-like sound that has been used for meditation for thousands of years is the sound of the “Om” mantra.

In essence, drones include any sound that is:

1. Unbroken - the sound does not stop and start, and
2. Relatively unchanging in pitch.
Drone sounds are not usually melodious, and they have no discernable tempo, but they do have other important qualities that must be musically pleasing. For example, drones often have a “texture” that can be described with words like “smooth”, “fine”, “soft” or “coarse”, and a timbre that can be described with words like “celestial”, “warm” or “complex” just to name a few. The pitch of a drone must not be too high or the drone may become shrill and tiring, and it must not be too low or the drone may become imperceptible on some stereo systems.

A drone may also be made up of many layers of sounds, and when these sounds harmonize with each other they become deeply hypnotic and most pleasurable to listen to.
Drones may also be used to provide a hypnotic foundation to a piece of music that contains other elements such as chimes, nature sounds or instrumentation. Here are a few examples. They are all very different musical experiences, but they are all founded on a drone:
Untold Depths

When it comes to meditation music and hypnosis music, drones can extremely useful. Their sustained, soothing tones encourage feelings of safety and help to wash away persistent thinking. Unlike music that is more melodic and dynamic, drones will not overstimulate your mind or distract you while you are trying to relax. On the contrary....drones can actually draw your mind into a very deep state of relaxation.


The sounds of nature

Since the dawn of time, we have been surrounded by the wonderful sounds of mother nature. It’s only been during the last few decades or so that man-made music has become commonplace…and along with it has come all the noise and cacophony of modern industry and media. We have become cut off from the sounds of our natural environment, and bombarded by sounds that create stress.
Listening to the sounds of nature reminds us that we are a part of a greater whole. The sound of birds in the morning, the sound of crickets in the evening…these are just some of the sounds that remind us that our life extends beyond the four walls that surround us at our home or office. The ebb and flow of waves on a beach, the sound of wind in the trees…these soothing sounds are innately peaceful, and listening to them can help reconnect you to "the bigger picture" of life.


Brainwave entrainment music

I’m sure you have already heard of the word “brainwaves” and you may already know that brainwaves can be measured with a machine called an electroencephalograph (EEG).
When you are awake and alert, higher frequency brainwaves tend to dominate, whereas lower frequency brainwaves become more pronounced when you are drowsy or asleep. An EEG allows us to measure these changes, just as it allows us to measure the brainwave frequencies of a person who is in a state of deep relaxation. With this in mind, we come to the whole point of brainwave entrainment music...
Certain sound frequencies, when combined in specific ways, can be used to alter your brainwaves so as to induce a state of deep relaxation.
Brainwave entrainment is more simple than it might sound at first. Think of it this way...imagine you are holding two tuning forks of the same pitch. If you strike one of them and hold it close to the other, they will both vibrate at the same frequency. Brainwave entrainment or "brainwave synchronization" is similar to this. It relies upon the "frequency following" response, a naturally occurring phenomenon that explains how the human brain tends to change its dominant frequency towards the frequency of an external stimulus.
As you might expect, brainwave entrainment doesn’t just work with any old sound. To give rise to the frequency following response, specific types of sounds must be used. Here is a brief introduction to the two most common types of sounds for brainwave entrainment.


Binaural Beats

Binaural Beats or “binaural tones” are an auditory effect that is created in the brain when two tones of slightly different frequencies are played separately into each ear.
Your brain is very sensitive to small variations in the frequency of sounds, and to the way those sounds reach your ears. When you listen to binaural beats, your brain is subjected to an effect that it perceives as a constant fluctuation in the directionality of the sound.
The rate of this fluctuation can be controlled by the use of specific sound frequencies. For example, by playing a tone of 200 Hz in the left ear, and 210 Hz in the right ear, a fluctuation of 10 Hz is detected by the brain.
The difference between the two frequencies could be called a “sub harmonic” – a sound that is below the threshold of human hearing. However, this sub-harmonic binaural frequency may still be detected as a slight pulsing sound. This pulsing, or beating, is why we call them binaural “beats”.
Binaural beats cause the brain to adjust its dominant frequency to match the sub harmonic frequency of the beating sound. This is what is known as the “frequency following response”.
In order to control the way the frequencies reach your ears, music that contains binaural beats must be listened to with headphones.  Binaural beats make a wonderful addition to music for meditation and hypnosis because they can actively induce a state of deep relaxation.


Isochronic Tones

Like binaural beats, isochronic tones are also used to stimulate the frequency following response.
In contrast to binaural beats, isochronic tones can be listened to without the aid of headphones. In essence, isochronic tones are simply a repetitive pulsing sound that encourages the frequency of your brainwaves to synchronize with the frequency of the isochronic tones. Much like the hypnotic effect of a pendulum clock, isochronic tones are a simple but effective way to encourage various states of relaxation and meditation.

Brainwave entrainment tones like binaural beats and isochronic tones are usually blended into a piece of music at a quite volume so that they are not aurally overwhelming. Want to hear some examples? You can explore some of our own royalty free brainwave entrainment music here.


Relaxation music - it's deep stuff!

Not only is relaxation music something that you can appreciate on a sensory level, it’s exciting to realize that it can be created in such a way that it has a very direct and powerful effect on the activity of your mind. It is with this excitement that I apply the principles of psychoacoustics to the music I compose for meditation and hypnosis. As you have by now come to realize, relaxation music can be a pretty deep subject!

But for some reason, music for meditation and hypnosis is often regarded as being “simple”. Sure enough, most meditation music is not as complex as say, a full orchestral composition, but like many things in life that appear simple on the surface, there can be a whole genre of science going on underneath the hood. We've only just begun to explore that science in this article.

While we're on the subject of science, I'd like to finish by highlighting the fact that music cannot be entirely reduced to a set of scientific principles. I certainly do take the principles of psychoacoustics into account when I compose music, but they are hardly the dominant force in my creative process. Inspiration and intuition - two rather undefinable, unquantifiable factors - play a much larger role.