| Unit | Measures | Scale | Human Perception | |------|----------|-------|------------------| | | Perceived loudness | Linear (2 sones = twice as loud) | Directly proportional | | Decibel (dB SPL) | Sound pressure (physical) | Logarithmic | Not proportional | | Phon | Loudness level | Logarithmic (matches dB SPL at 1 kHz) | Scale for matching loudness |
This formula is an idealization. The exact sone value for a given dB SPL depends on frequency, as the human ear is not equally sensitive to all frequencies.
The sone is related to the decibel, but the relationship is non-linear. A common approximation used for converting sound pressure level (phon, a unit of loudness level) to sones is:
| Unit | Measures | Scale | Human Perception | |------|----------|-------|------------------| | | Perceived loudness | Linear (2 sones = twice as loud) | Directly proportional | | Decibel (dB SPL) | Sound pressure (physical) | Logarithmic | Not proportional | | Phon | Loudness level | Logarithmic (matches dB SPL at 1 kHz) | Scale for matching loudness |
This formula is an idealization. The exact sone value for a given dB SPL depends on frequency, as the human ear is not equally sensitive to all frequencies. sone definition
The sone is related to the decibel, but the relationship is non-linear. A common approximation used for converting sound pressure level (phon, a unit of loudness level) to sones is: | Unit | Measures | Scale | Human