Understanding Sound
If you want to get the full benefits of experiencing sound healing as a meditation practice, therapy, or are interested in knowing how to perform sound healing, it is important to know the basics of the medium, sound. The body has a tendency to be more responsive when the mind is informed of what is going on. Once you become aware of something, the body often accepts and integrates the new information more easily and efficiently. For this reason, I’ve outlined some basic principles that are at work in sound and sound healing.
Sound is an energy wave that passes though molecules. The molecules compress and we hear those compressions as
different frequencies depending on the rate of the compression on our ear drum which translates to neural impulses produced by the cilia in our ear and sent to the brain. The rate of compression is a result of the length of the actual sound wave. Some sound waves are meters long (sub-bass frequencies) or extremely short, millimeters and smaller (ultra high frequencies).
The simplest sound wave is a Sine Wave. The graph of a sine wave looks like an “S” laying on its side. It is that artificial, lifeless tone we hear when the TV alerts us to an emergency broadcast. “BOOOOOOP.” Other basic sound waves are the Triangle Wave and Square Wave, so named for their shapes. They only contain odd harmonics (discussed below). The Saw-Tooth Wave contains both od and even harmonics, but has a dittinct buzzing sound. Timbre is the quality of a sound as distinct that depends on the relative strengths of the different frequencies and mix of odd and even harmonics. It is why an oboe sounds like an oboe and a clarinet sounds like a clarinet for example.
One phase, or complete cycle of a sound wave is the length from the beginning to the end of the “wave, measured in actual distance. The number of complete cycles and the distance it travels in one second determines its frequency, measured in Hertz (Hz). 1000 HZ means the sound wave cycled 1000 times in one second. That’s fast, short, and a high pitch. Some of us can hear up to 18,000Hz. Other animals can hear much higher, like dogs and with the delightful whistle that drives them crazy.
We also feel sound as the sound waves stimulate the molecules in our body as well. We feel different sounds in different places because different frequencies behave differently with the different parts of our body, like bass frequencies in our gut for example. But there is a lot more going on than just physical sensations or hearing.
Wave Dynamics
Because sound is a wave, it follows the laws of wave dynamics. A brief explanation is to compare the behavior of sound waves to that of ocean waves. When two waves meet at their crest (highest point), a wave twice the size is produced. This is called amplification. When two waves meet at their low points, a trough is created. This is called diminution. When one wave is at its high point and the other at the low point and they are of equal value, a flat surface is produced on the water. This is called Phase Cancelation. In terms of sound, this is called silence. In Germany they use this technology on some of their highway systems. Microphones pick up the sound of the traffic and speakers feedback the inverse into the air, thus silencing the sound of the traffic.
One important concept related to phase cancelation is the phenomenon called Phasing. This occurs when there are two frequencies of slightly different lengths. 440HZ and 450HZ for example. As they are both generated the will gradually shift of out phase with one another, and then back into phase. This creates a palpable percussive effect or pulsating sensation. This effect is a result of the frequencies cancelling each other out periodically. In the realm of sound healing I refer to this a Sonic Dissonance, and I will return to the concept in the section on Sound Healing.
Acoustics
Following the water allusion, picture a pond. The surface is still but then you drop a pebble into it and rings of concentric circles spread out from the center. If you drop another pebble into the water at another location, it too will generate concentric circles spreading out. But as the circles increase in size they will start to overlap and interfere with one another following the laws of wave acoustics outlined above. This is the basis for the study of sound acosustics. A room is to the pond, though three-dimensional as opposed to a flat surface. One can imagine how complex acoustics can become in even a simple place. The point of origin, i.e., a voice, instrument, or speaker, sends out sound waves that interact with the space in a myriad of ways. They fill the space, interact with one another, bounce of the walls and ceiling, get absorbed into the materials, curtains, carpets, furniture, our bodies, etc…
This complex interaction of sound waves in a space can produce very interesting, and exciting phenomena known as Overtones and Undertones. To understand these we need to discuss the Harmonic Spectrum. Every pitch, every frequency naturally produces a Harmonic Spectrum of sound. It is the same for every pitch and is the basis of the Natural Tuning System developed my Pythagoras. To elaborate would be to embark upon a narrative of the origin of music theory, of which I am certainly capable of doing, but which is out of the scope of this text.
The sounding pitch is called the Fundamental. The fundamental generates a parabolic curve consisting of Harmonics that continues to infinity (theoretically). One composer friend of mine believes that white noise, which is the sound of all frequencies at once, contains the Divine. His theory is derived from the infinity of the harmonic spectrum. The first harmonic is called the 2nd Partial. It is the octave above the fundamental. The second harmonic is the 3rd Partial. It is the interval of a Perfect 5th above the 2nd Patial. The harmonics continue to be numbered in this way up to infinity. Each subsequent partial is half the intervalic size of the previous. See the chart. We typically track up the 16th Partial. After that the semitone differences get smaller and smaller and eventually imperceptible.
When sound waves interact in the air they sometimes naturally highlight overtones and undertones that can be heard, even though no physical source is actually producing the sounds. These can be produced with intent, as with Overtone Singing, which will be discussed later.
Another phenomenon you can encounter and easily reproduce is the Standing Wave. We said before how sound waves have actual lengths. Whatever frequency can mathematically fit perfectly in the space between the origin and a wall, for example, will naturally be amplified. You can go into a bathroom with tile walls (best for sound to bounce back) and test different pitches by sweeping through a range. You will feel and hear one that is stronger than the rest. That is the Standing Wave frequency. It is also referred to the Resonant Tone of the space. We each have a Resonant Tone, the pitch or frequency that resonates with our body the most and best. Muscle testing can determine what it is for an individual. Within any given enclosed space there is always a “Sweet Spot” where the acoustics are the best.
Sympathetic Resonance is another important acoustic phenomenon. Sympathetic Resonance occurs naturally as a result of similar wavelengths of a frequency striking an object that can produce those same wavelengths. Here is a practical example: there are a violin and a guitar. If the G String on the guitar is strummed, the G String on the violin will begin to vibrate as well. A famous, yet tragic example is the Tacoma Narrows Bridge in Washington State. This bridge was originally a suspension bridge. In 1940, strong winds that matched the resonant tone of the bridge caused the bridge to vibrate with sympathetic resonance resulting in its collapse.
Resonance has reached the popular vernacular. When people say “I resonate with that, they imply that their energies/thoughts are sympathetically resonating with the things/concept. And when people feel instantly connected to someone they just met, it is a sign that they share similar energetic vibrations. To be technical, pheromones are scents with specific frequencies, so the “chemistry” between two people is a simple matter of resonance.
Continue to the next post, Sound as Healing” where we will look at physiological effects of sound on the body and sound as healing…