Where 396 Hz comes from
396 Hz is the first tone of the modern Solfeggio set and carries the syllable "Ut" - the original first note of the medieval solmization scale from the hymn "Ut queant laxis" (the same scale that gave us do-re-mi). The modern frequency assignments were introduced in the 1990s by Joseph Puleo, who derived them through numerology from the Book of Numbers.
In sound-healing tradition, 396 Hz is the grounding tone: practitioners assign it to the root chakra (Muladhara) and use it at the start of a session to "clear" fear and guilt before working upward through the other frequencies. Musically it sits close to G4 (392 Hz in standard tuning), about 17 cents sharp.
What to expect when listening
As a pure tone, 396 Hz is a warm mid-range pitch - lower and rounder than the brighter 528 Hz, without being bassy. Practitioners typically play it softly for 5-15 minutes during meditation, breathwork, or journaling, sometimes alternating with the other Solfeggio tones in ascending order.
From a scientific standpoint there is no peer-reviewed evidence for chakra-specific or emotion-specific effects of individual frequencies; the demonstrated benefit of practices like this comes through relaxation and focused attention, which are genuinely valuable. If a steady, warm drone helps anchor your practice, this tone does that job well - use the sine wave for purity or triangle for a softer body.