Initializing Python runtime and loading acoustics models.

Sound Level Calculator (Experimental)

Convert between sound pressure and sound power levels, combine sources, and summarize octave-band spectra.

Tool Purpose & README

Loading README...

Inputs

Start with the minimum inputs. Full Analysis unlocks source stacking and octave-band detail.

1) SPL / SWL Conversion

Define the source model and distance used to translate between sound power and pressure.

?
?
?
?
?
?
?
2) Combine Sources

Sum multiple incoherent sources using logarithmic addition.

?
3) Octave-Band Spectrum

Provide octave-band SPLs to compute overall levels and spectrum plots.

?
?
?
?
?
?
?
?
?
Full Analysis uses defaults for advanced fields unless you override them.
Waiting for calculation inputs.

Configuration Summary

Conversion mode, source model, and band weighting will appear here.

Primary Results

Sound Pressure Level (SPL)
--
Sound Power Level (SWL)
--
Show advanced results

Propagation Detail

Geometric Spreading Loss
--
Directivity Gain
--

Combined Source Level

Combined Level
--
Provide levels to combine sources.

Octave-Band Summary

Overall Level (Z)
--
Weighted Overall (A)
--
Switch to Full Analysis to review source summation and octave-band outputs.

SPL vs Distance

Scale: log
Run a calculation to plot the distance sweep.

Octave-Band Spectrum

Weighting: Z
Provide octave-band values to plot the spectrum.
Switch to Full Analysis to enable the octave-band spectrum plot.

Tool Overview

Summary text will load from the calculation docstring.

What You Can Do

  • Convert between sound power (SWL) and sound pressure (SPL).
  • Estimate geometric spreading and directivity adjustments.
  • Combine multiple incoherent sources using decibel addition.
  • Summarize octave-band spectra and apply A/C weighting.

Inputs & Outputs Glossary

Definitions are pulled directly from the calculation docstring.

Inputs

Outputs

Sound Level Fundamentals

Sound pressure level (SPL) describes the pressure fluctuation at a receiver, while sound power level (SWL) describes the total acoustic power emitted by a source. The conversion depends on distance, geometric spreading, and directivity. When multiple sources contribute, their energies add, not their decibel values.

Octave-band data captures how energy distributes across frequency. Weighting curves (A and C) apply frequency-dependent offsets to approximate human hearing sensitivity.

Equations

Implementation Notes

  • Geometric spreading uses simplified constants (11 dB for spherical, 8 dB for cylindrical) based on ISO 9613 guidance.
  • Directivity gain is applied as 10 log10(Q) for the selected mounting condition.
  • Octave-band weighting uses standard octave-band approximations from IEC 61672.
  • Line and plane models are idealized for quick estimates rather than full propagation modeling.

References

  • ISO 9613-2: Acoustics - Attenuation of sound during propagation outdoors.
  • IEC 61672-1: Electroacoustics - Sound level meters (frequency weighting).
  • ISO 226: Normal equal-loudness-level contours.
  • Bies, Hansen, and Zander. Engineering Noise Control (5th ed.).