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.

Ear Separation Meters

A finite measured or assumed value greater than or equal to 0, expressed in m.

Speed Meters Per Second

A finite measured or assumed value greater than or equal to 0, expressed in m/s.

The implemented rule is: Simple maximum interaural time difference in microseconds using a straight ear-to-ear baseline and sound speed.^[1]

Microseconds

The calculated microseconds, expressed in us.

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 straight-baseline estimate omits diffraction around the head and frequency-dependent auditory processing.

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.

• Absorption Required For Target Rt

  Metric Sabine equivalent absorption area required for a target RT60: 0.161V/T.

• Acoustic Impedance Medium

  Characteristic specific acoustic impedance rho*c for a uniform medium.

• Acoustic Intensity From Spl

  Plane-wave free-field intensity from sound-pressure level, assuming the conventional 10^-12 W/m² reference.