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.

First Hertz

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

Second Hertz

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

The implemented rule is: Sum combination-tone frequency from two input sinusoid frequencies.^[1]

Sum Hertz

The calculated sum hertz, expressed in Hz.

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.

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.

• Difference Tone Frequency

  Absolute difference combination-tone frequency from two input sinusoid frequencies.

• Beats Frequency

  Beat rate in hertz from the absolute frequency difference of two close tones.

• Absorption Required For Target Rt

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