Thursday 9th February 2012 – The Amazing Binaural Audio

Binaural recording is an idea quite new to me. @TOther_Simon introduced me to it at the end of last year, and ever since I have been having quite a few thoughts about it’s potential. I have been making some exploratory recordings which have come out very well but to get a well-put-together experience of binaural recording put some headphones on and watch the video below:


Fast Tube by Casper

How Does it Work?

As you will be able to hear, binaural recording is a way to get what may be called 3D sound. Conventional two channel recording (stereo sound) is the product of trying to get realistic sense of space into recordings by working from the fact we have two ears. Different signals go to both the right and left speakers to enable a more realistic sound, meaning sounds can be positioned within the 180 degree arc between the speakers. Using reverberation (echo), we are also able to position the sounds up close or further away. However, stereo recording does not account for the physical intricacies of our hearing. As you know, we are able to place sounds from all around us without looking and stereo recording only allows this to happen in front of us (if we are facing speakers), or inside our heads (if we are listening to headphones). Our brain uses the fact that there is a certain distance between the two ears, as well as information about the very shape of our ears to allow us to pinpoint where in the world a sound is coming from; you can hear sounds from behind you as well as in front of you.  Binaural recording, takes account of these facts to trick your brain into thinking that what you are listening to is actually occurring in the three dimensional space around you. Of course, our ears are on the sides of our heads and not on our faces so to get the full effect from a binaural recording, it is best to use headphones. The effect is more realistic on headphones that have a clear emission of sound from across the audio spectrum but it seems to work pretty well even when using the cheapest headphones.  Achieving this is very simple: use a dummy head with realistic ears containing microphones or use tiny microphones that resemble earphones and be the dummy head yourself!

Where Would You Use Binaural Recording?

So, this is all interesting and gimmicky, but how can binaural recording be used? Well, as you will see from the above video, the guy who made it is promoting a video game that uses binaural recording to make the game experience more immersive. With the rise of portable entertainment with iPhones and iPads etc, the rise in use of headphones could really facilitate more widespread use of binaural audio. This technique could mean more realistic simulations for different kinds of training, or maybe use in film to place the audience in the same space as the actors.  This technique has also been used to record bands too, and was apparently used as far back as the 60’s. Some test recordings I made of me playing my acoustic guitar got a very rich and full sound without having to mess around with mic placement at all.  For me though, the most fantastic thing about binaural recording is the possibility to take an audience somewhere that would be totally impossible to go to, like the video game example. You could mix the real and the imagined and blur the line between them to get closer to the ultimate escapism.

Please do put ten minutes aside to listen to the example of an audio composition located at the bottom of this web page. It’s nothing to do with my own work but you wont regret it… very cool.  I’m raring to go do some experimenting now…

Please feel free to contact me if you would like to add such ideas to your own projects.