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Acoustics
Spherical Sound Spreading
Enter values in the stated units. Example inputs are provided to help you explore the method.
Results
Your results will appear here after calculation. Changing an input clears the previous result.
Method & assumptions
- Ideal full-sphere spreading: I = P/(4πr²), then L = 10 log₁₀(I/Iref).
- Example: 0.01 W at 10 m gives about 7.958 × 10⁻⁶ W/m², or 69.01 dB relative to 10⁻¹² W/m².
- Assumes an isotropic point source in a lossless free field. Excludes reflections, ground effects, barriers, atmospheric absorption and near-field effects.
- Use radiated acoustic power, not electrical input power. This model is not a noise-exposure assessment.