What Frequency is my Singing Bowl?

June 3, 2024 - by Shakti

 

I often hear the question: “What frequency is my singing bowl?” Well, actually, a Tibetan sound bowl produces several frequencies. So, the “struck tone” of a singing bowl is a contradiction in terms because when you strike a singing bowl, it produces a chord or interval. The predominant tones we hear in singing bowls are the fundamental (the lower tone) and the overtone (also called the mid or rim tone). In some medium-sized and most large singing bowls, there is a mid-tone as well as a rim tone (these are sometimes called the first and second overtones), with layers of sub-harmonics in between.

The relationship of these two frequencies in almost every Tibetan singing bowl is a flatted fifth interval, also known as a diminished fifth, augmented fourth, and most famously, a Tritone. This interval was referred to as “the Devil’s Chord” and was widely believed to be banned by the Medieval Catholic Church, although a Catholicism.org article debunked that as a myth.

The Tritone is three steps apart from the mid-tone (hence the name), and it can be in any key. The bad rep of the interval stems from the inherent tension between its notes: it sounds somewhat dissonant compared to other intervals, such as the sweetness of a third or a sixth. Whereas it might create tension in Western instruments such as a piano or violin, in singing bowls, it is richly layered, softening the dissonance and creating a meditative soundscape, closely related to the fourth (the key of Gregorian chanting) and the fifth (the Fibonacci interval).

Binaural Beat Frequencies

The graduated diameters of singing bowls produce layers of rich additional overtones, which, when heard binaurally, create beat frequencies that alter our brain wave pattern from the Beta state to an Alpha state and, in some instances, to Theta. Dr. Jeffrey Thompson, founder of the Center of Neuroacoustic Research wrote:

Usually, binaural beats are the result of two separated tones interacting together to create the binaural beat…. two speakers or two headphone speakers. But in a Tibetan Bowl, both tones arise from how the bowl is shaped creating different diameters in the same bowl, equaling different tones coming out of the same bowl.

When two of these bowl tones are within the critical bandwidth to create a binaural beat -two tones interacting – but not from two different separated sources… from one source superimposed on top of one another…they are therefore monaural or monophonic. So, Tibetan Bowls present a unique instance where binaural beats are not from two separated stereo sources, but are both superimposed on top of one another from a single monophonic source: Monophonic Binaural Beats.

Dr. Thompson wrote a white paper on the effects of binaural beats on brainwaves entitled “Acoustic Brainwave Entrainment with Binaural Beats” which is a great resource to learn more on the physics of brainwave entrainment.

Singing Bowl Tonal Differences

So unlike Crystal singing bowls, which are almost pure sine wave with a 3rd interval harmonic (or 4th interval, depending on the bowl), Tibetan singing bowls are rich in layered frequencies. The lower tone of the bowl (the fundamental) is produced by rubbing a leather mallet around the outside wall of the bowl; the female overtone (the bowl’s highest voice) bowl is produced by pressing the wooden part of the mallet along the outside edge of the bowl’s lip.

There is usually also a mid-tone present in medium-sized to large bowls, with multiple frequencies in between. This tone will usually come up when you begin to play a medium-sized bowl around the lip, and then after the bowl is warmed up, it will resolve to the female overtone and jump an octave. With some high-wall (“Jambati”) type singing bowls, you can most often isolate this tone with a leather mallet.

How to Meter Your Bowl’s Frequencies

The most accurate way to measure a bowl’s frequency is to isolate it, and then run it through a tuner app on your phone or computer. There are many to download, from Spectroid, Black Cat Systems (this link is for IOS, but they make them for Android too), Sonic Tools, and many others. Of these, Black Cat Spectrum Analyzer is the only one that I know of that can list all of the bowls’ major harmonics simultaneously. For most of the other apps, you’ll have to play a clean, isolated tone first, let it peak, and then start to decay before the tone will even out enough for the tuner to lock in and measure it. But remember: every singing bowl frequency is still a moving target. Any measurement we take is only a snapshot of a moving wave form.

The Effect of Bowl Shapes on their Sound

The frequencies produced by the bowl are determined by the bowl’s diameter, shape and density of its metal. All three of these factors affect each other. Generally speaking, the larger the bowl’s diameter the deeper sounding the bowl. But the density of the metal counts, too: the thicker the bowl, the higher the pitch.

Dr. Thompson once observed that the graduated diameters of the bowl actually produce a singing bowls’ harmonics. That explains why the slope of the bowl’s wall can affect how many harmonics there are in a bowl. For example, smaller Cup bowls which are 4 – 5″ diameter will only have two distinct harmonics. “Thadobati” type (medium sized) singing bowls usually have three: the fundamental, the a mid-tone, and the overtone. A Jambati, Manipuri, or Cobrebati type singing bowl with a broad, sloping base will have many more audible harmonics, and sounds more gong-like in timbre, than bell-like in timbre. The deeper the frequencies, the lower they become in volume.

Because the ancient ones were handmade, their construction varies slightly with each and every bowl. Their intervals are like voice patterns; no one voice is exactly the same. So the pitches of the bowls were determined at the time they were made and cannot be altered unless you subtract metal from the bowl (by sanding the basin of the bowl, for example). We believe that ancient bowl makers also may altered the bowls’ frequencies by creating “hatch marks” in the sides of the walls.

The Effect of Singing Bowl Frequencies on the Body

As noted, Tibetan singing bowls are handmade, and so are as unique as we are. Each of us is a unique, resonating entity. So, the effects of singing bowl frequencies will depend on the bowl and on the body! But assuming the bowl’s harmonics are in tune, some potential benefits include:

1. Relaxation and Stress Reduction: The gentle tones of Tibetan singing bowls can induce a state of deep relaxation, helping to reduce stress and promote overall well-being. Their soothing sound vibrations can calm the nervous system and encourage the body to enter a state of relaxation.

2. Pain Relief: Sound therapy, including the use of singing bowls, has been shown to help alleviate pain by promoting the release of endorphins, the body’s natural pain relievers. The vibrations of the bowls may also help to reduce muscle tension and inflammation, providing relief from physical discomfort.

3. Enhanced Meditation and Mindfulness: The meditative quality of Tibetan singing bowl sounds can deepen one’s meditation practice and enhance mindfulness. The rhythmic vibrations can help to quiet the mind, allowing for a deeper connection to the present moment and an increased sense of inner peace.

4. Improved Sleep Quality: Listening to Tibetan singing bowls before bedtime may promote better sleep quality by relaxing the body and mind. The calming effects of the sound vibrations can help to induce a state of tranquility, making it easier to fall asleep and experience more restful sleep throughout the night.

5. Emotional Release and Healing: The vibrations of Tibetan singing bowls can facilitate emotional release and healing by encouraging the release of stagnant energy and emotions stored in the body. Many people report feeling a sense of emotional catharsis and relief after listening to the soothing tones of Tibetan bowls.

Overall, the effects of Tibetan singing bowl frequencies on the body are thought to be holistic, encompassing physical, mental, emotional, and spiritual aspects of well-being. While more research is needed to fully understand the mechanisms underlying these effects, many individuals find them to be powerful tools for relaxation, healing, and self-discovery.

Knowing Your Bowl’s Frequencies – Why it’s Important, and Why It Isn’t

Knowing the frequencies of your bowl is really helpful if you want to add bowls to your collection, if you’re playing bowls with Western instruments, or if you’re looking for a bowl that resonates with a certain Chakra or Meridien. But apart from that, try not to attach too much importance on, for example, if the bowl is exactly Western concert pitch, 432 Hz., or resonates to planetary frequencies. Much too often people pay more attention to finding a bowl in a certain tuning than properly assessing the quality of the bowl’s sound.

How does the bowl’s sound affect you? Feel it in your body. If your breathing slows and your muscles soften, you’re probably listening to a bowl that resonates with you. The quality of the sound will be where the rubber meets the road in sound healing: whether it will create harmony or discordance. So, once you know the frequencies of your bowl, just let it go! Thank your left brain for retaining that information and get back the business of becoming one with the sound.