General Acoustics News

Ultimate 3D Audio

Ultimate Surround Sound?

In our previous post, we looked at the potential uses for 3D audio and virtual reality.  This post is going to show you just how powerful 3D audio can be. You might want to get your headphones ready for this one.

There are three binaural tracks below for you to listen to (with headphones on). I’m sure that you will notice the difference between these tracks and normal audio as soon as you listen.

Quite an impressive effect isn’t it? What is even more impressive is that no clever software was used in these recordings. Only a pair of binaural microphones and a handheld recorder. Your brain does the rest of the work using head related transfer functions (HTRFs) – image below from wikipedia.

Binaural recordings are not new, in fact the phenomena was first used in the Theatrophone, 136 years ago! This device was first demonstrated by Clement Ader in 1881 at the world expo. The Theatrephone was a telephonic distribution system used in France, and later in Europe to broadcast opera and theatre performance in binaural stereo.

Dummy heads are used in laboratories to create binaural recordings, and in-ear microphones are available to the general public. But it is surprising to find that that the use of the technique is not more widespread (136 years later).

This is now changing (in the field of acoustics at least), as algorithms have been developed to emulate the complex HRTFs carried out in our brains. We can expect to see realistic 3D audio in the coming years.

If you would like to record your own 3D audio, there are a number of in-ear microphone pairs now available. We have used the Roland CS-10EM binaural microphones, with the Roland R-05 handheld recorder.


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