Definition
The range of sound-wave frequencies that the human ear can detect, generally between approximately 20 hertz and 20,000 hertz (20 Hz to 20 kHz).
Plain English
The frequencies of sound that people can actually hear. Anything below this range is too low to hear, and anything above is too high to hear.
Context Anchor
Seen in aircraft noise, vibration, headset audio, warning-tone, and maintenance discussions.
Derivation
From the Latin sonus, meaning sound. So sonic frequencies are simply the frequencies of sound — specifically those a human ear can pick up.
Why Pilots Care
Cockpit audio systems, intercoms, radios, and warning tones are all designed to operate within sonic frequencies so the pilot can actually hear them. Knowing the range helps when troubleshooting audio problems or understanding why certain warning tones are pitched the way they are.
Grounding Statement
If you can hear the tone or noise with your ears, it is in the sonic frequency range.
Intuition Check
Do not read “sonic” here as “near the speed of sound.” Here it means “related to hearable sound.”
Example Sentence 1
The intercom amplifies signals across the full range of sonic frequencies so voices come through clearly.
Example Sentence 2
Headsets filter out unwanted sonic frequencies while preserving clear radio transmissions.