| Feature | Phon | Sone | |--------|------|------| | Scale type | Logarithmic (like dB) | Linear | | Zero point | 0 phons (hearing threshold at 1 kHz) | 1 sone = 40 phons | | Doubling meaning | Not applicable | 2 sones = twice as loud | | Best for | Comparing loudness across frequencies | Quantifying how much louder one sound is over another | | Example use | "This 80 Hz tone is 70 phons." | "This fan is 4 sones — twice as loud as that 2-sone fan." |
Advanced algorithms, such as those defined in or DIN 45631 , compute Sones using a complex model involving: phons and sones
Sones directly reflect human perception. If you increase a sound's physical intensity by 10 dB (which doubles the sone value), listeners will say it sounds "twice as loud." | Feature | Phon | Sone | |--------|------|------|
A 50 dB tone at 100 Hz (low rumble) sounds much quieter than a 50 dB tone at 2000 Hz (mid-range) — even though their physical sound pressure is identical. Why? Human ears are not flat frequency sensors. We are most sensitive to frequencies between 2–5 kHz and less sensitive to very low or very high frequencies. Human ears are not flat frequency sensors
