3D sound reconstruction

[2] As an alternative, the head-related transfer function can be used on the sound source signal to pan its convolution to each of the loudspeakers depending on their direction and location.

This allows the calculation of the energy of signal for each speaker through evaluation of sound in several control points within the listening room.

Each microphone measures an impulse response from a time-stretched pulse signal for various time frames with various sound sources.

The system also convolves the head-related transfer function with the impulse response from the signal recorded by the microphones and the energy is adjusted per the original time frame of the sound signal, and an additional delay is added to the sound to match the time frame of the impulse response.

[1] These measurements are processed by Tomographic reconstruction to reproduce the three-dimensional sound field, and then the convolution back projection is used to visualize it.

This method is applicable primarily to ultrasound and to lower sound pressures, often in water and in medical imaging.

If the wave number is changing throughout the medium, this method cannot reconstruct the three-dimensional sound field as accurately.