5.4 Binaural Techniques in Spatial Audio

Binaural techniques are loosely defined to be methods which aim to control directly the sound in the ear canals to match a recorded real case or with a simulated virtual case. This is done by careful binaural recordings, or by utilizing measured or modeled head-related transfer functions (HRTFs) and acoustical modeling of the listening space.

5.4.1 Listening to Binaural Recordings with Headphones

The basic technique is to reproduce a recorded binaural sound-track with headphones. The recording is made by inserting miniature microphones in to the ear canals of a real human listener, or by using a manikin with microphones in the ears [Bla97]. This recording is reproduced by playing the recorded signals in the ears of the listener. This is a very simple technique in principle, and can provide effective results. A simple implementation is to replace the transducers of in-ear headphones with insert miniature microphones, to use a portable audio recorder to record the sounds of the surroundings, and to play back the sound with headphones. Already without any equalization, a nice spatial effect is achieved, as the left–right directions of....