ToolsSound, propagation & hearing
Loudness: sone, phon & level change
Convert phon and sone, and see how much louder a level change sounds.
Phon ↔ sone
phon
sone
How much louder is a level change?
dB
- Perceived loudness factor
- 2×
- Sound pressure / voltage factor
- 3.16228×
- Sound intensity / power factor
- 10×
Above 40 phon, loudness doubles every 10 phon (Stevens' rule). Below 40 phon a power-law approximation is used. Phon equals dB SPL only at 1 kHz; at other frequencies use equal-loudness contours (ISO 226).
How it works
A 10 dB increase is commonly perceived as about twice as loud, although it is ten times the power. Phon is loudness level (dB SPL of an equally loud 1 kHz tone); sone is loudness on a ratio scale.
Formulas
- N = 2^((L_N − 40) / 10) sone (L_N ≥ 40 phon)
- loudness factor = 2^(ΔL / 10)
Found a mistake or have an idea for this tool?
Suggest a change