How "3D audio" works!

This is a blog post for my Systems in Emergent Digital Practices class at University of Denver. I will be classifying this as my Biological Systems explanation.

 Here is an ear.

Here is an ear.

The term 3D audio has been thrown around a lot recently. In some cases, it can seem to be more of a gimmicky buzzword than a legitimate function. The particular snake-oil known as 'virtual surround sound' has been used in countless times, for, more often than not, gaming headsets. For this they use realtime in-line processing to create what some might perceive as a more valuable listening experience out of either surround signals, or just an effect to the stereo channels (or even just make it louder with more bass).

But for this post, we will be talking about how audio recorded specifically for that purpose can trick your brain into thinking that it has entered a soundscape provided only by stereo headphones. Not 'surround sound'. Just pure stereo trickery of the production process.

Binaural Recording

 Here is a binaural microphone.

Here is a binaural microphone.

There are a few different ways of achieving this goal. The tactic first would be to use binaural microphones. This is where two omnidirectional microphones are placed inside of a mannequin head with detailed humanoid shaped ears. Since the audio is recorded in a way that almost directly replicates the human auditory experience, it sounds as if you are in the room that the recording took place in. In this regard, it uses your own biological senses to create what is an audible illusion. A great example of the effects of binaural recording is this video below. I must admit, at one point, I stopped breathing briefly due to one specific effect they used. You have been warned.

An early YouTube viral phenomena that utilized binaural recording techniques. This was created by QSoundLabs.

Crazy, right?

The Naturespace Approach

For one particular company known as Naturespace, they have devised a rather ingenious idea based on photographic depth of field. Their approach is to use microphones capturing the foreground, midground, and background of a natural soundscape. You can hear more about it in this link.

 What the Naturespace people probably see everyday. Still from The Sound of Music. All rights reserved to 20th Century Fox. Please don't sue me. ¯\_(ツ)_/¯

What the Naturespace people probably see everyday. Still from The Sound of Music. All rights reserved to 20th Century Fox. Please don't sue me. ¯\_(ツ)_/¯

So how is this a biological system?

Because it both emulates and stimulates a biological system. It just cuts the middleman out of the equation (the middleman being your ears), and replaces it with another middleman (that other middleman being microphones). But what process must it go through to be a system?

  1. Sound comes out of a source
  2. Sound goes into the microphones
  3. Gets processed and recorded
  4. Gets distributed
  5. Gets played back into headphones
  6. Gets processed by your brain (just as normal sound hitting your own ears would)
  7. Tricks you