Andy Coates Blog

I have been getting allot of search queries and questions about my Virtual Haircut post from people wanting to know how it was done. With sound engineering being part of my "day job" I thought I would give an in-depth explanation into how you can create your very own virtual barbershop.

How It Works
Human beings have a highly developed sense of hearing which helps us keep our balance and stability in every day life. Because of the way our ears are shaped and where they are positioned on our head, the timbre of the sound which when it reaches our eardrums can change depending on which direction it is coming from. From minute changes and volume differences between ears our brains can work out which direction sound is coming from. Not only that, our brains can also recognize sound which has been reflected off surfaces which tells us about our surroundings too. For example, if you were blind folded you would automatically know if you were in a large open room with bare walls or a small furnished room. This is because we have also learned to associate surroundings with sounds and our brain automatically unconsciously relay's this information to us, so without really thinking about it we can "sense" our surroundings.

Neumann Recording Dummy

Creating a binaural recording is a relatively simple process of trying to re-create circumstances in which sound reaches the ears. To do this a dummy head is generally used with microphones placed either side of the head to simulate the ears. When sound is coming from one side of the head, the closest microphone will pick up the "direct" sound whilst the furthest microphone will pick up mainly "reflected" sound. This simulates how the sound would reach your ears in real life, so when played back through headphones you can "trick" the brain into thinking that it is hearing direct and reflected sounds instead of a stereo recording. The brain automatically, subconsciously informs your consciousness of your surroundings depending on what the recording is. For example, when you listen to the virtual haircut you can hear that it is in a wood paneled room, because you probably have experience of what a wooden room sounds like you brain tells you that you are in those surroundings.

You can create your own binaural recording using small microphones attached to either side of your head and recording each microphone on its own channel, i.e recording one mic to the left input of your recorder and the other to the right input. Make sure you know which is which as it affects your perception during playback. As a rule of thumb the more realistic the recording head, and higher quality the microphones the better, and more realistic recording you will get!

So to summarize how it works, basically binaural recordings work by recording sound in a stereo pair, mimicking the same way the human ear picks up sound!

Enjoy!!

Andy