Skip to main content

Aluminum vs Steel and the Importance of Harmonics

This is the second part of information from Dr. John Beaulieu. In this post John discusses why he selects aluminum alloy over steel for tuning forks. 


I chose aluminum tuning forks because of their potential to ring overtones. When I first worked with tuning fork manufacturers in the early 1970’s to create a tuning fork that would ring all the overtones they thought I was crazy. Tuning fork manufacturers look down upon tuning forks that ring overtones. Their goal is to eliminate overtones because they believe the higher the quality of a tuning fork the less overtones it will produce. They are correct when it comes to making a tuning fork for tuning an instrument or science classes. They are not correct when it comes to making a quality tuning fork for the healing arts.

Over time we experimented with different aluminum alloy formulas to get a hardness that would sound the complete overtone series. This was not an easy process. Today the less expensive aluminum tuning forks use softer aluminum which does not sound the complete overtone series. To my knowledge, only BioSonic tuning forks are the only tuning forks that ring the complete overtone series. BioSonic tuning forks are designed to be congruent with my research and years of experience with sound.

What are overtones? 

Overtones are the "hidden" sounds of music. Normally we think of a sound made by a musical instrument as "one note". For example, if you play C on the flute and the same C on the violin; they are both the same note C. Our ears know that the two C's sound different even though they are the same note. It is the sounding of different overtones above the note C that gives each instrument its distinct sound or tonal color.

The importance of overtones in sound healing is not new. The image of Jacob's Ladder is often associated with the ascension of overtones. Jacob's Ladder begins on earth and rises to heaven. Earth is a metaphor for the fundamental tone and each step of the ladder represents a different overtone ascending to heaven. The ancient scholars of the Kabbalah believed that angels lived in the spaces, known as intervals, between the ascending overtones. The intervallic spaces between overtones were known by the ancient Taoists as the Mysterious Mountain Passageways leading to angelic kingdoms.

Playing, singing, and listening to overtones has long been a method of healing and spiritual awaking. Buddhist chanters in Mongolia and Tibet sing overtones embedded with sacred mantras. They resonate overtone sound in different sinus cavities and spaces within their cranium while chanting. Many cultures have produced bowls that when they are tapped or rubbed produce different overtones. The most well known bowls are the Tibetan Singing Bowls. The Russian Composer Alexander Scriabin in the early 1900's believed that sounding overtones would bring forth a new era and unite Heaven and Earth. His last composition, Mysterium, was to be played in India using etheric bells hung from clouds that sounded very high pitched overtones like wind chimes. Scriabin visualized himself sitting on earth listening to overtone voices of Devas or Spirit Angels that would bring forth a new era of enlightenment.

Why are overtones so important? 

Overtones stimulate the neural net through tactile stimulation as well as auditory nerve conduction. When overtones are sounded they create thousands of pulsations within pulsations that massage the listener within an ever changing environment of sound waves. When we listen to the overtones, we hear them through our skin as well as with our ears. Simultaneously, a cascade of structural and physiological events occur in our body as the overtone waves spread throughout our brain causing millions of neural synaptic junctions to seek out resonance with the different intervallic overtone relationships.

I first discovered this through experimentation in an anechoic chamber. Recently research has been published that is congruent with my phenomenological findings. A neuroscience team headed by Dr. S.J. Bensmaia of the University of Chicago has demonstrated that our sense of touch and feeling is much like our sense of hearing. Normally our ability to touch and feel is described as a grid of receptors in our skin that transmits information to our brain. Dr. Bensmaia found that our skin is highly receptive to vibrations and that these vibrations produce corresponding oscillation effects in our nerves. Experimental subjects were able to differentiate microtonal frequencies through touching and feeling. This would explain how my deaf patients were able to feel sound waves on their skin and know exactly what music was being played.

(Mackevicius, EL, Best M.D., Saal H. P., Bensmaia SJ. Millisecond Precision Spike Timing Shapes Tactile Perception. Journal of Neuroscience, 2012; 32 (44): 15309 DOI: 10.1523/JNEUROSCI.2161-12.2012)

Is there a mathematics to overtones? 

Mathematically overtones are a series of tones starting from a fundamental tone and ascending infinitely in pitch. They are based on the simple numerical sequence 1,2,3,4,5,6,7 ……………… n. Overtone frequencies can be calculated through numbers and ratios based on this sequence.

Have you recorded overtones? 

Yes. I have dedicated a lot of time to working and recording overtones. When you play an instrument or tap tuning forks together overtones sound naturally in different dynamics. I became very interested in overtones as individual sounds with equally dynamic values. The last composition on my CD Calendula “A Suite For Pythagorean Tuning Forks” is called Angelic Conversations. The title reflects the belief that light beings, angels, and devas live in the intervallic spaces of the overtone series. It is called conversations for several reasons. The first is that entering into the web of sounding overtones your neural net will adapt and pick out the overtone intervals that are most attractive to you. Within these intervals one can discover the presence of the divine or sacred.

In modern terms, we call this neural plasticity. The sounding of overtones stimulates the neural net and lights up the brain stem through the production and release of nitric oxide gas. The constant movement and firing of synapses will form a pattern based on your focus within the sound. This is an unconscious process, however it is possible for the experience of overtone intervallic relationships to surface into our conscious awareness and be perceived as a dialogue with divine beings. This is the basis of much mysticism in music. I believe this is what draws us again and again to music and why music is a part of every religion and spiritual discipline.

The second reason for the title Angelic Conversations is to let the listener know that there are other conversations. During the 1990’s I became so immersed in exploring overtones that I created the CD Spirit Whistles. Spirit Whistles is an entire CD of overtone explorations using specially designed overtone whistles, synthesizer tuned overtone sine waves, and Peruvian Whistles.

If I own steel tuning forks or another brand of aluminum tuning fork do they have healing value? 

Yes. Steel tuning forks are tuned and when tapped on our knee and brought to the ears will have the same effect as aluminum tuning forks in terms of balancing the nervous system. However, they will not ring overtones and even with a knee tap our aluminum tuning forks will ring subtle overtones. So even though one will get a sense of harmonic balance, one will not receive the added healing benefits of overtones.

With other brands of aluminum tuning forks it is buyer beware. Recently we tested aluminum tuning forks from China and Pakistan. They used a very soft aluminum alloy that contained lead. The tuning forks were not heat treated and overtime they will lose their tune and due to the softness of the alloy they dropped many overtones. I believe even these tuning forks have a healing value. I would not recommend them however they make sound and ring some overtones. I believe this is better than no sound.

Final thoughts

BioSonic tuning forks are high quality musical instruments designed for healing. They are extensions of many years of experience and research. All of my research and writings on sound healing are public. They are my contribution to the healing arts and sound healing field. All healers can use the principles I discuss and create sounds that work with those principles. BioSonic tuning forks are one way in many of doing this. My goal has always been to ensure that they are a high quality sound healing tool based on accountable standards."