Frequency Atlas
Musical Frequencies

F4

349.23 Hz
Note: F4
Cosmic Octave Color
Derived visible color (390 nm)
Display swatch #9f3de9
EstablishedMusical Standard
Evidence Level
Established
Source Count
1
Last Reviewed
March 23, 2026

Directly measured, standardized, or well-supported in mainstream scientific or technical literature.

This entry documents a musical reference or standard. It should be read as an acoustic and musical reference rather than a biological claim.

Review the evidence model

Musical note F in octave 4. Mid to treble range.

Period
2.86 ms
Wavelength
98.2 cm
Nearest Note
F4 (0¢)
Claim Type
Musical Standard
Cosmic Octave Color
Derived visible color (390 nm) · #9f3de9
Source
Equal temperament tuning system (A4 = 440 Hz)

Sources

Equal Temperament Tuning System
108 atlas references

The twelve-tone equal temperament reference used for note-frequency lookups throughout the atlas.

Standard equal-temperament note table with A4 = 440 Hz.

Harmonic Series

musicequal-temperamentoctave-4