The science · Solfeggio
174 Hz, explained
174 Hz is the lowest of the nine solfeggio values, a set first put forward in the 1970s. Popularly linked with grounding, it is a description of what people say about it, not of an effect. In Sonor it is a carrier pitch: it changes the note you hear, not the band.
What the research says
The numbers were derived in the 1970s by Joseph Puleo from a pattern of verse numbers in the Bible's Book of Numbers (Science Feedback, 2022). 174 Hz is not among the six values in the earliest lists, so it is a later addition. The review did not locate who first added it. A fact-check found no scientific or clinical evidence that any solfeggio frequency regenerates the body or removes toxins.
A PubMed search for 174 Hz combined with music, sound, tone, solfeggio, healing or acoustic returned four records. Two are unrelated. One (Dabiri et al., 2026) used 174 Hz as the carrier for a delta binaural beat in 20 students, but it did not compare carriers, so it says nothing about 174 Hz itself. The other (Mehta and Uggini, 2026) exposed zebrafish embryos to 174 Hz as a noise-safety check and found no significant adverse effects. That is a safety study in fish, not a study of benefit.
No peer-reviewed study was located that tested a 174 Hz tone for any effect on people.
How Sonor uses it
174 Hz is a named carrier pitch for the isochronic tone. It is the lowest named value and sits just above the top of the 60 to 170 Hz carrier slider. Choosing it changes the note you hear. The pulse rate, and so the band, stays the same. See What are carrier frequencies? for what a carrier does.
You can hear Sonor's tones on the listen page.