Binaural & tones
528 Hz: What It Is, Why People Listen, and What the Evidence Says
528 Hz is everywhere, from meditation playlists to sleep videos, usually with very big promises attached. Here is the calm, honest version.
Binaural & tones
Solfeggio Frequencies Explained: What Each Tone From 396 to 852 Hz Is Said to Mean
Stress builds up, and a steady tone can help some people slow down. Here is what the solfeggio tones are, the moods they're associated with, and an honest look at the claims.
On this page
Stress has a way of filling every quiet moment. Some people reach for music, some for silence, and a growing number for solfeggio frequencies: simple tones with names like 396 Hz or 528 Hz. If you’ve wondered what they are, and whether the claims are real, here is a calm overview.
Where the solfeggio frequencies come from
Solfeggio refers to the sol-fa syllables singers have used since medieval times (ut, re, mi, fa, sol, la). The modern list of solfeggio frequencies is a much newer idea. It was first promoted in the 1970s, popularized by books in the late 1990s, and spread through meditation and relaxation music online.
There’s no historical record of these exact frequencies in early music. And while each tone has picked up a meaning, those meanings come from that tradition rather than from research.
The tones and their mood words
Here is the set, with the calm mood words Solbox uses for each, and how people commonly use them.
| Tone | Mood word | How people use it |
|---|---|---|
| 396 Hz | Release | Letting go at the end of a hard day |
| 417 Hz | Reset | A fresh start in the morning or between tasks |
| 432 Hz | Calm | A soft, warm background; also an alternative tuning |
| 528 Hz | Renewal | Slow evenings and rest (more on 528 Hz) |
| 639 Hz | Connection | Calm conversations, journaling, time with family |
| 741 Hz | Clarity | Light focus work, layered with noise |
| 852 Hz | Centering | Stillness, breathing and quiet attention |
What about the claims?
You’ll find very big claims online about what individual tones do to the body or mind. They aren’t supported by good evidence, and Solbox doesn’t make them.
What research does exist is small and early. A 2019 pilot study compared music tuned to 432 Hz with the standard 440 Hz and found slightly lower heart rates and higher satisfaction with 432 Hz, in 33 people. Research on related “brainwave” sounds like binaural beats is also mixed, as a 2023 systematic review found.
The fair summary: solfeggio tones are a listening preference, like a favorite playlist. That’s fine. They don’t need to be medicine to be useful.
Why a simple tone can still help
- It gives your attention a place to rest. A steady sound is easier to settle into than silence for many people. See why silence makes focus harder.
- It becomes a ritual. The same tone each evening is a signal to slow down.
- It masks small noises, especially when layered with rain or a noise color.
How to listen
- Choose by mood word, not by claim: Calm for evenings, Clarity for light work.
- Keep the volume low and layer the tone over a soundscape or noise.
- Give it 15–30 minutes, with a timer so it ends on its own.
- If a tone feels piercing, switch to a lower one like 396 or 432 Hz.
In Solbox
Solbox has all seven tones, each labelled with its Hz and mood word and paired with its own soundscape and haptic pattern. 396 and 417 Hz are free; the rest come with Solbox Pro. Browse them on the solfeggio frequencies page.
Frequently asked questions
What are the 7 solfeggio frequencies?
The classic six are 396, 417, 528, 639, 741 and 852 Hz. Many apps and playlists add 432 Hz, an alternative tuning, which makes seven.
Which solfeggio frequency is best for stress?
People who use solfeggio tones for winding down often choose the lower ones, like 396 or 432 Hz, which feel softer. There's no research showing one tone reduces stress better than another.
Are solfeggio frequencies ancient?
The syllables come from medieval singing practice, but the specific frequency list is modern. It was promoted from the 1970s and became widely known from the late 1990s.
Can I use solfeggio tones while working?
Yes, at a low volume and layered with a noise color or soundscape. Brighter tones like 741 Hz are often used for focus, softer ones for evenings.