Understanding Sone to dBA: A Guide to Loudness and Verification
Because the sone scale is linear (double the sones = double the loudness) and the dBA scale is logarithmic (double the energy = +3 dB), you cannot convert a single number without knowing the frequency content of the noise.
This feature provides a single source of truth for manufacturers or engineers to convert subjective "sones" into objective "dBA" values. sone to dba verified
| Unit | Objective vs. Subjective | Key Conversion Formula | |------------|--------------------------|--------------------------------------------| | Decibels | Objective (physical) | dB SPL = 40 + 10·log₂(sones) | | Sones | Subjective (human perception) | Sones = 2^(dB SPL -40)/10 |
| Sones (Loudness) | Approximate dBA (SPL) | Perceived Loudness Example | | :--- | :--- | :--- | | | 28.0 dBA | Rustling leaves, whisper-quiet PC fan | | 1.0 sone | 33.0 dBA | Quiet library, high-end bathroom fan | | 1.5 sones | 36.5 dBA | Refrigerator hum (quiet) | | 2.0 sones | 39.0 dBA | Very quiet residential AC vent | | 2.5 sones | 41.5 dBA | | | 3.0 sones | 43.0 dBA | Normal conversation (soft), average range hood (low) | | 4.0 sones | 46.0 dBA | Bird chirping, quiet office background | | 5.0 sones | 48.5 dBA | | | 6.0 sones | 50.0 dBA | Rainfall, dishwasher running | | 7.0 sones | 51.5 dBA | | | 8.0 sones | 53.0 dBA | Normal conversation (medium volume) | | 10.0 sones | 55.0 dBA | Vacuum cleaner (distance) | | 12.0 sones | 57.5 dBA | Busy traffic inside a car | Understanding Sone to dBA: A Guide to Loudness
verify these ratings so consumers know the "1.0 sone" label actually translates to a quiet environment. A-Weighting Accuracy
When you need to verify a sone-to-dBA conversion, answer these questions: The formula used to convert is generally:
For verification, it's helpful to have a reference chart:
(33.2 * 0) + 34 =
Because sones are linear and dBA is logarithmic, there is no single, simple direct formula. However, the accepted industry standard, often used by Sengpielaudio and ventilation companies, is based on the relationship to phons (another loudness unit). The formula used to convert is generally: