Use this calculation for a first-order acoustics estimate when the stated geometry, propagation model, averaging convention, reference quantity, and SI units match the measurement or design problem.

Sones

A finite measured or assumed value greater than or equal to 0.

The implemented rule is: Phon level from loudness of at least one sone, using 40+10 log2(sones).^[1]

Phon

The calculated phon.

This is an idealized calculation rather than a complete acoustic simulation or measurement. Reflections, boundary conditions, directivity, damping, frequency dependence, near-field behavior, background noise, transducer response, temperature, humidity, and geometry can change a real result. The implemented power-law conversion applies only at and above the stated 40-phon or one-sone boundary and is not a full equal-loudness contour model.

Confirm important results with calibrated measurements or a model that includes the actual geometry, materials, boundaries, source directivity, and frequency-dependent losses. Preserve the reference quantity and weighting whenever a result is expressed in decibels.

• Phon To Sone Converter

  Loudness in sones from phon level for 40 phon or above: 1 sone at 40 phon, doubling every 10 phon.

• Cents To Ratio Converter

  Frequency ratio corresponding to a signed interval in cents.

• Hz To Mel Converter

  Frequency in mels from hertz using the common 2595 log10(1+f/700) scale.