Musical Frequencies
F#4
369.99 Hz
Note: F#4
Cosmic Octave Color
Derived visible color (737 nm)
Display swatch #9a232f
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 modelMusical note F# in octave 4. Mid to treble range.
Period
2.70 ms
Wavelength
92.7 cm
Nearest Note
F#4 (0¢)
Claim Type
Musical Standard
Cosmic Octave Color
Derived visible color (737 nm) · #9a232f
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
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.
F#1Musical Frequencies
46.25 Hz0¢
F#2Musical Frequencies
92.50 Hz0¢
F#3Musical Frequencies
185.00 Hz0¢
F#5Musical Frequencies
739.99 Hz0¢
F#6Musical Frequencies
1.5 kHz0¢
F#7Musical Frequencies
3.0 kHz0¢
musicequal-temperamentoctave-4