Sound therapy is based on the theory that our bodies and everything around us emanates a sound. This sound is more often that not above or below the frequency at which the human ear can actually hear and interpret it, but even if we cannot hear a sound, we can often feel it through vibrations. It is said that our bodies, including the organs and ‘chakras’, have their own unique sound which is perfectly balanced. However, this balance becomes disturbed by outside influences and by internal influences such as stress. When the body is unbalanced, it encourages poor health and disease. Sound therapy works with the aim of re-tuning our bodies using a variety of different sources including instruments, such as the didgeridoo, as well as tuning forks and singing bowls and things as simple as the human voice. The principles of working with sound in the healing process are resonance and harmony. As the sound waves enter the body, sympathetic vibrations occur in its living cells which help resonate and reinforce healthy organization. The high water content of the body's tissue helps to conduct sound and the overall effect is likened to a deep massage at the atomic and molecular levels. The human being is therefore likened to a very complex, unique and finely tuned musical instrument.