This is part of a series of articles by Garth Whitcombe, founder of TherapyMuse, that provides background information about the use of music in massage therapy settings.

The universe is a web of waveform frequencies, from seismic and extremely low frequency waves that are many kilometers wide to the infinitesimal electromagnetic range in the region of 5 quadrillion hertz.

We think of waves as the march of tides on a foreshore or the ripples of wind over still water. A vivid example of wave behavior is the pattern that results from a pebble being tossed into a still pond. Waves radiate in a circular pattern in all directions causing a temporary displacement of particles. The particles themselves remain unaltered. All that travels is the wave pattern.

Sound waves differ only in that while waves on water radiate across the surface, sound waves radiate three dimensionally in a spherical pattern, creating an expanding ball of waveforms. Such images bear uncommon similarity to waveforms in other mediums.

You may have experienced a waveform from the inside during the swirl of celebration at a sports event or rock concert. The spectators rise from their seats with arms upraised in perfect timing as ‘the wave’ sweeps around the stadium. In this remarkable phenomenon of spontaneous co-ordination, it should be noted that people move in space in an orderly fashion, they stand up, but they don’t change seats. The participants of the wave return to their starting position once the wave has passed. The wave continues through the crowd until the momentum of enthusiasm dies down and then it peters out.

A wave can be visualized as a moving pattern traveling through a support medium such as air or water or a conductive solid. We experience much of our sensory interaction with the world through different kinds of waves. Light waves stimulate the visual cortex and sound waves resonate in our inner ear, while radiant energy is registered as warmth on our skin.

Wave forms are calibrated in three ways; wavelength, amplitude and frequency. Wavelength measures the interval of repetition of the wave pattern. Amplitude measures the size of the wave and in the case of sound, the greater the amplitude the louder the sound.

Volume is measured in decibels. The frequency of a waveform is the number times a complete pattern passes a given point and it is measured in cycles per second or hertz. Audible sound occupies a small bandwidth of the waveform spectrum, in the frequency range from around 16 hz to 20,000 hertz and with wavelengths that span 2 centimeters to 20 meters.

Within the audible range of sound we find the specific waveform vibrations that generate musical tones. The lowest audible tones produce vibrations at around 30 per second. The highest tones produce many thousands of vibrations per second.

The sound spectrum spans a much wider range than what we hear, from the infrasonic to the ultrasonic frequencies. These inaudible sounds can be felt physically in the rumbling of lower registers and in some cases of extreme volume piercing high frequencies can be heard up to around 40,000 hz. Sound is created by pressure vibrating molecules in longitudinal waves that move steadily further and further from the source.

Unlike light waves, sound waves cannot exist in a vacuum, they are dependant on a medium of transmission. The speed of sound waves is determined by the supporting medium. Sound in air travels at 1,235 km/h, in fresh water at 5,328 km/h and in granite at 21,600 km/h.

Light and electromagnetic waveforms move at 300,000 km/second.

Sound is created by vibrations of a sonorous body, most often caused by a collision of masses. The hit of a drum stick on a drum skin, the motion of a plucked string, wind over an aperture or reed, the vibration of vocal chords. These vibrations of mass are transferred to the atmosphere, through the influence of their vibrations on the localized atmospheric pressure setting up oscillations in the air particles. The waves radiate outward relative to their amplitude, or the force of the original reaction. The atmospheric vibrations that are the carrier waves of sound become the sensations we perceive as sound through pressure interactions with the delicate mechanisms of the inner ear.

Until sound waves enter the ear they are merely pressure differentials, the raw code of sound, like the code that runs a computer program. It is the ear that decodes these pressure signals and imbues them with the significance we experience as sound.

The difference between the sound waveforms we consider noise and those we hear as noise is the characteristic of the pattern. Noise is a discordant jumble of tone, a tangle of frequencies, waveforms overlapping, filling all the space like a scribbled page compared to a line drawing. Tone (sound we define as musical) has a regularity of pattern. Sound waves are periodic oscillations. Waveforms that maintain a consistent, regular shape will translated by the ear as music. Tone can be defined as a sound waveform that constantly returns to its state of origin over an exactly equal time period. Regularity of waveform denotes music, irregularity denotes noise.