A scientific article I stumbled upon scanned subject’s brains using fMRI whilst they listened to voices being played over headphones. The voices were either played in stereo (inside the head) or using 3D audio (outside the head). The aim was to find the neural substrate for the perception of voices outside the head (in what we might call external auditory space) in an effort to better understand auditory hallucinations of that type. You can find the article for free here. Very interesting.

One other large emerging application of 3D audio that you might not be aware of is for hearing aids. People who require hearing aids at the moment have sounds simply amplified and they are unable to know the direction of where the sounds came from. This makes situations such as a dinner party almost impossible. Normal listeners at a dinner party are able to follow one conversation and ignore the other voices due largely to the fact that the brain knows where the sounds are coming from (this is the so-called Cocktail Phenomenon). Once this ability is lost, as with a hearing aid, all the voices are mashed together and it is impossible to follow a conversation. A hearing aid with 3D audio amplifies the sounds around the listener and at the same time provides a sense of where the sounds are coming from.

Have a listen to this demo (USING HEADPHONES ONLY) to see what it is like have a hearing aid with and without 3D audio. The demo starts without 3D audio and then 30 seconds in it switches to 3D audio, you will hear it don’t worry (think of what it’s like to have hallucinations of people talking while you listen). Focus on trying to understand the different talkers. Again, you must use headphones:

Visit the site and watch the short movie (or watch it below) for some amazing audio effects. Remember to wear your headphones.

Enjoy

The GSMA Mobile World Congress (formerly 3GSM World Congress) represents the world’s largest exhibition for the mobile industry with a stimulating and insightful congress that brings together prominent leaders and personalities from mobile operators and equipment vendors, as well as Internet and entertainment professionals. Arkamys will have a stand at the GSMA Mobile World Congress showing off its latest technology from the 16th to the 19th of February. http://www.mobileworldcongress.com/overview.shtml

It is an example of what is called a ‘binaural recording‘. A dummy head, with tiny microphones stuck inside its ears, is used to record an acoustic environment such as a person cutting your hair or a band playing in a room. You then listen to the binaural recording over headphones and it is as if you were sitting at the position of the dummy head at the moment of the recording. The best way to really understand the process is to just watch and listen to these examples:

YOU MUST USE HEADPHONES FOR THE FIRST EXAMPLE!

‘Snakecharmer-Binaural‘ by Ottmar Liebert

John Q. Walker’s talk (7 minutes 45 seconds in) entitled ‘Re-creating great performances’ from the EG 2007 conference posted on TED

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