2026-04

639 Hz forms an exact 3:4 perfect fourth with 852 Hz and sits between D♯5 and E5. Its numbers, intervals to the other Solfeggio tones, where the figure came from, what research says, and our tracks.

396 Hz forms an exact 3:4 perfect fourth with 528 Hz and sits just above G4. Its numbers, intervals to the other Solfeggio tones, where the figure came from, what research says, and our tracks.

963 Hz, the highest of the nine tones, checked by calculation: nearest note, cycle, wavelength, intervals, why it sounds sharp as a pure tone, where the figure came from, what research says, and our tracks.

What are Solfeggio frequencies? This beginner’s guide covers all 9 tones, their meanings, how to choose the right one, and practical tips for daily use.

528 Hz checked by calculation (16 cents above C5, the 432 Hz tuning clash, the 3:4 with 396 Hz), where the "love frequency" name came from, what the small studies can and cannot support, and our own measured 528 Hz tracks.