What's Really Happening in a Sound Bath: Frequencies, the Earth's Hum, and Why I'm Bringing Tuning Forks Into the Treatment Room

Have you ever noticed how a single sound can change the whole feeling of a room? The dishwasher beeps three times and your shoulders creep up a little. Rain starts tapping on the window and something in you softens. Nobody had to explain anything to you. Your body heard it and responded before your mind had a chance to weigh in.

That's the territory of sound healing, and it's been on my mind a lot lately. We have sound baths coming up at the Sanctuary, I've started using tuning forks in my sessions, and in the next couple of weeks I'll be introducing meditation immersion sessions. So I wanted to sit down with you and walk through what's actually going on when you lie on a mat and let sound wash over you.

In this post, we'll look at what a frequency really is, how different frequencies seem to interact with the body, the story of the Earth's own frequency, the instruments used in sound healing and how each one feels different, and what the research is beginning to catch up on. Then I'll share why tuning forks have found their way into my energy healing sessions and the new scalp ritual.

First, what is a frequency?

Everything that makes a sound is vibrating. A frequency is simply how many times that vibration repeats in one second, measured in hertz (Hz). A low hum might vibrate around 100 times a second, while a bright chime might vibrate thousands of times a second.

Our ears pick up roughly 20 to 20,000 Hz. Below that range we stop hearing sound and start feeling it, which is why a deep gong or a drum seems to land in your chest rather than your ears. Sound healing works in both of those places: what you hear, and what you feel.

And here's something worth sitting with for a moment: a huge amount of sound in the world happens completely outside what we can hear. Just because our ears can't catch it doesn't mean it isn't there, moving through the air, the water, the ground, and us.

• Below our hearing (infrasound): elephants talk to each other in low rumbles that can travel for miles, and whales call across entire oceans. Thunderstorms, ocean waves, earthquakes, and volcanoes all give off infrasound too. People can't hear it, yet many describe sensing it as pressure, unease, or a feeling in the body they can't quite name.

• Above our hearing (ultrasound): bats find their way through total darkness by bouncing high-pitched calls off the world around them, and dolphins do something similar underwater. A dog whistle sounds silent to you and perfectly clear to your dog. And ultrasound is how many of us first saw our babies, sound waves too high to hear, painting a picture of what's happening inside the body.

If an elephant can feel a message through the ground and a bat can see with sound, it's not much of a leap to wonder what our own bodies might be picking up that our ears never register.

Here's where it gets interesting. Your body runs on rhythms too. Your heart beats in a rhythm, your breath moves in a rhythm, and your brain produces electrical patterns that researchers group into bands by frequency:

• Delta (about 0.5–4 Hz): deep, dreamless sleep

• Theta (about 4–8 Hz): drowsiness, deep meditation, and that drifting space right before sleep

• Alpha (about 8–13 Hz): calm, relaxed wakefulness, eyes closed and mind quiet

• Beta (about 13–30 Hz): active thinking, focus, and problem-solving (and, when it runs too long, replaying tomorrow's to-do list at 2 a.m.)

• Gamma (above 30 Hz): high-level processing and integration

One of the ideas behind sound healing is called entrainment, the tendency of rhythms to fall into step with one another. Hang two pendulum clocks on the same wall and they'll eventually swing together. In the same way, slow, steady, repetitive sound invites the brain and body toward slower rhythms. Researchers are still mapping exactly how this works in people, but if you've ever been rocked to sleep, or noticed your breathing slow down next to someone who's already asleep, you've felt a version of it.

The Earth has a frequency, too

This is the part I find most fascinating.

The Earth is surrounded by a natural electromagnetic signal called the Schumann resonance. Around 2,000 thunderstorms and roughly 50 lightning flashes every second send energy bouncing through the space between the Earth's surface and the ionosphere, and that space rings at a fundamental frequency of about 7.83 Hz.

Look back at that list of brainwaves for a moment. 7.83 Hz sits right where theta meets alpha, the same range our brains drift into during deep relaxation and meditation.

Researchers have noticed this overlap, and some are now exploring whether our brains and bodies interact with the Earth's electromagnetic rhythms. It's not an easy thing to study. The Schumann resonance is an electromagnetic rhythm rather than a sound, and it's very faint next to all the electrical activity of the brain. But "we haven't measured it yet" is not the same as "it isn't there." Meditative and healing traditions have talked about attuning to the rhythms of the Earth for a very long time, and science is only now building the tools to ask the question.

What I find so meaningful is this. Our nervous systems developed on a planet humming at that frequency, and when we finally slow down, our own brain rhythms wander back into that same neighborhood. Personally, I find it hard to believe that means nothing.

The frequencies you'll hear about most

If you've spent any time in sound healing spaces, you've probably seen certain numbers come up again and again. Here's what they are, and what we actually know about them:

• 432 Hz: an alternative to the 440 Hz tuning most modern music uses. Several small studies, including a 2019 pilot study with 33 people, found that music tuned to 432 Hz lowered heart rate more than the same music at 440 Hz. Many people describe 432 Hz as warmer and easier to sink into, and the early research is starting to reflect that.

• 528 Hz: often called the "love frequency," and one of the most beloved tones in sound healing. A few small studies have looked at 528 Hz music and stress, and one recent study found lower levels of a cellular stress marker in students who listened to it while facing exams. It's early, but it's exactly the kind of finding that makes me want to see more.

• 128 Hz: a common weighted tuning fork frequency used directly on the body. Back in 2003, researchers proposed that sound supports relaxation partly through nitric oxide, a molecule that helps blood vessels relax. That mechanism is still being explored, and it's a big part of why this fork is so loved in bodywork.

• Solfeggio frequencies (including 396, 417, 528, 639, 741, and 852 Hz): a set of tones drawn from sacred music tradition, each associated with a particular intention, like releasing fear or opening to connection. These come to us through spiritual and energetic practice, carried forward because people experienced something in them. Most haven't been studied closely yet. That's a gap in the research, not a verdict on the tones.

So where does that leave us? With a lot of promising threads, and a lot of questions science simply hasn't gotten around to answering yet. I've worked with the body long enough to know that "not yet proven" and "doesn't work" are two very different things. Massage was calming people for thousands of years before anyone discovered the nerve fibers that help explain why, and I suspect sound will turn out to have a similar story.

The instruments, and how each one feels

Every instrument in a sound bath has its own personality. Here's a little tour of what you might hear, and feel, at the Sanctuary:

• Tibetan (Himalayan) singing bowls: hand-hammered metal bowls with a warm, complex tone layered in overtones. Because the metal is never perfectly uniform, each bowl has its own voice. They can be played around you or placed right on the body, where you feel the vibration move through you.

• Crystal singing bowls: made from quartz, these produce a pure, clear tone that seems to hang in the air for a long time, and they're often tuned to specific notes. Where Tibetan bowls feel earthy and textured, crystal bowls feel bright and spacious.

• Tuning forks: the most precise instruments of the group. Unweighted forks are struck and held near the ears to be heard. Weighted forks carry small weights at the ends of the prongs so the vibration lasts longer, and they're placed on the body to be felt.

• Gongs: a wash of sound with so many overtones that the thinking mind can't keep track of them all, which is often exactly when it finally stops trying.

• Chimes, rain sticks, and ocean drums: softer textures that echo the sounds of nature, the sounds our bodies have likely found soothing for a very long time.

• The voice: humming and chanting naturally lengthen the exhale, and a long, slow exhale is one of the most dependable ways we know to nudge the body toward rest and digest.

So what does the research say about sound baths?

Most of the research so far focuses on singing bowls. In a 2017 study, 62 adults took part in a singing bowl meditation and afterward reported significantly less tension, anger, fatigue, and depressed mood. One of my favorite details is that people who had never tried this kind of meditation before saw an even bigger drop in tension than people who had. So if you've been hesitant because you "don't know how to meditate," that might actually work in your favor.

This research is still young. A 2020 systematic review found only four peer-reviewed studies on singing bowls, noted that the results leaned positive, and called for larger, better-designed studies before making formal recommendations. A more recent review found that singing bowls may help ease anxiety and depression and improve sleep across different groups of people. The science is catching up, and the direction it's heading is encouraging.

Here's how I hold all of it. The studies matter, and I love following them. But sound has been part of healing practices in cultures all over the world for a very long time, and the people who developed those practices were working from observation, intuition, and what they saw happen in the people in front of them. Then there are all the people today who walk out of a sound bath feeling different than when they walked in. That lived experience is information, too. Science is one beautiful way of understanding the world. It isn't the only one.

Why I've started using tuning forks

I didn't find tuning forks in a textbook. I experienced them first. I was at a crafting workshop, of all places, and partway through, the teacher used a tuning fork on each of us. It was amazing. I could feel the vibrations all over my body, and I could feel my muscles release tension. That experience stayed with me, and it's a big part of why they're in my treatment room now.

You already know how much I love the research on slow, gentle touch and the way it signals safety to the body. Tuning forks add another layer to that conversation. When a weighted fork is placed on the body, you receive both at once: the touch and the vibration, traveling through tissue in a way you can still feel after the tone has faded from your ears.

That's why I've started bringing tuning forks into my energy healing sessions, and why they're part of the new scalp ritual launching October 21. In the ritual, they become one more way of telling an overworked nervous system that it's safe to set things down for a while.

Come experience it

Reading about sound is a little like reading about the ocean. Helpful, but nothing like getting in.

If you're curious, our upcoming sound baths are a beautiful place to start. You don't need to know how to meditate, you don't need to bring anything but yourself, and you certainly don't need to be struggling to deserve an hour of quiet. And keep an eye out, because meditation immersion sessions are coming to the Sanctuary in the next couple of weeks. Find out and enroll in classes here.

References

• Bozok, Ü. G., Özcan, G. B., Bayraktar, B., & Özen, D. (2026). Acute music-frequency exposure modulates salivary stress and neurotrophic markers in young adults: A randomized controlled trial. Brain and Behavior, 16(5). Read the study

• Cai, Y., Yang, G., Liu, Y., et al. (2025). Therapeutic effects of singing bowls: A systematic review of clinical studies. Integrative Medicine Research. Read the study

• Calamassi, D., & Pomponi, G. P. (2019). Music tuned to 440 Hz versus 432 Hz and the health effects: A double-blind cross-over pilot study. Explore, 15(4), 283–290. Read the study

• Goldsby, T. L., Goldsby, M. E., McWalters, M., & Mills, P. J. (2017). Effects of singing bowl sound meditation on mood, tension, and well-being: An observational study. Journal of Evidence-Based Complementary & Alternative Medicine, 22. Read the study

• NASA Goddard Space Flight Center. Lightning-made waves in Earth's atmosphere leak into space (Schumann resonance). Read more

• Salamon, E., Kim, M., Beaulieu, J., & Stefano, G. B. (2003). Sound therapy induced relaxation: Down regulating stress processes and pathologies. Medical Science Monitor, 9(5), RA96. Read the study

• Stanhope, J., & Weinstein, P. (2020). The human health effects of singing bowls: A systematic review. Complementary Therapies in Medicine, 51. Read the study