Schumann Resonance (Fundamental)
Directly measured, standardized, or well-supported in mainstream scientific or technical literature.
The underlying cycle is measurable, but the audible tone is an octave-transposed mapping used for comparison, listening, and practice rather than a naturally audible emission.
Review the evidence modelThe fundamental Schumann resonance at ~7.83 Hz is an electromagnetic standing wave in the cavity between Earth's surface and ionosphere, excited by lightning discharges. Falls in the alpha-theta brainwave border.
Sources
Used for atmospheric resonances, Earth-ionosphere cavity behavior, and related geophysical frequencies.
W.O. Schumann (1952) and later geophysical literature.
Historical Use
Used in sound healing and brainwave entrainment, sometimes called the "Earth's heartbeat"
Octave Ladder
Every audible octave of this frequency — the same tone, higher and lower.
Nearby in the Atlas
Entries within ±35 cents of this tone when reduced to the same octave — candidates for pairing or comparison.