A Binaural Break-in
I recently undertook the task of completing my very first bona-fide, binaural mix experiment… Call me a late bloomer.
The reproduction of binaural audio has been around since the dawn of time (factually sometime in the late 19th century) but it has never really been favoured as a means to reproduce and consume audio, until recently.
Thanks to advancements in the fields of VR, immersive technologies and gaming, commercial interest in 360 ˚spatial audio and binaural sound reproduction has made a full resurgence. And with major consumer platforms like Youtube, Apple Music and Facebook implementing spatial audio technology and offering free tools to anyone interested in experimenting with it, it’s never been easier and more cost effective to create your own immersive audio experience.
With binaural audio once again ‘in bloom’, let’s jump into a few cool binaural recording tools that will help anyone, including late bloomers like me, deliver a suitably acceptable binaural mix.
The Ubiquitous Dummy Head
If you are wanting to capture binaural audio in its purest form, then the dummy head will undoubtedly be your greatest asset. It quite literally resembles a human head, with two omnidirectional microphones placed within its ears. This piece of tech is designed to mimic the way we humans hear the world through providing aural information relating to the distance and direction of a perceived sound source.
Record a static scene on a park bench or a town square with a dummy head and you’ll be transported back to that same environment of sound over and over again, provided you are wearing headphones of course. There are a range of dummy heads on the market today, most famously, the Neumann KU-100.
The Neumann KU-100. Image courtesy of Neumann.
PS: If you are aren’t in the habit of spending £7000 on microphones, there are other binaural microphone options available such at the Soundman OKM II or the 3Dio Free Space. And of course, there is always the option of making your very own DIY dummy head. I made one for less than £35 and I’ll introduce you to him in my next post.
Another way to create a more immersive soundscape is with an ambisonic microphone. Without getting into too much detail right now, ambisonics is a method used to record sound on a 3D, 360˚ plane. It’s a full sphere of sound coming to a centre point, which would be the microphone, or in the instance of it being used in a binaural reproduction, you.
There are a multitude of ambisonic mics out there, the most notable of which would arguably be the tetrahedral Sennheiser Ambeo VR and the Rode NT SF-1.
The Rode NT SF-1. Image courtesy of www.rode.com
Personally, I took quite a liking to the idea of recording ambisonic atmospheres to use in a binaural reproduction, so I splurged a little on a portable recorder called the Zoom H3-VR.
This handy little pocket device records and decodes ambisonic audio on the go. And while it doesn’t have the lowest self-noise and resembles a Sputnik, I have really taken quite a liking to it. I used this recorder to help create the atmosphere in part of my binaural mix experiment.
The Zoom H3-VR, fondly referred to as the 'Sputnik'.
Now that we are more familiar with a few of the tools we can use to obtain some immersive audio, we need to bring it all together in a headphone mix that will transport us into a binaural realm. The secret? Spatialization.
Spatialization in a binaural mix is achieved through the use of binaural panning, reverb and occlusion between the listener and sound source. There are a few awesome plug in’s on the market today – some that are readily available to download for free. Check out the Facebook 360 Spatial Workstation. It’s popular for use in designing audio for 360˚ videos and VR.
A note on encoding and decoding
If you’ve recorded anything on a proper 1st, 2nd or 3rd order ambisonics mic, you will need an encoder to decode the audio from an ambisonics file format to a binaural stereo format that we can listen to on headphones, without losing to much of the immersive resolution. For this, I highly recommend the use of Soundfield By Rode. It has a user friendly interface, is straightforward to use and best of all, it’s a free download.
The 'favourite child'
The plug-in that absolutely blew my mind during my binaural mix experiment, was Dear Reality’s DearVR Pro. Holy moly. It takes spatialization to the next level with an easy-to-use interface that makes spatialisation and binaural panning truly idiot proof. Use this plug-in on any mono audio channel and place your audio wherever you want around the listener, at whatever distance, in whatever environment, with as much or as little occlusion as you desire and then output that audio in whatever format you require. It all happens in one, truly good-looking box. I love it.
DearVR Pro interface. Image courtesy of www.plugin-alliance.com
Lost | An Immersive Audio Experiment
When conceptualising my binaural mix experiment I decided to try a (very) short piece using video POV’s. My process was much the same as tracklaying for post-production, however the mix was focused on a binaural output.
I used 1st order ambisonic atmosphere tracks to create the feel of the surrounding environment and then quite simply created some mono channels and positioned the audio from those channels around the listeners head using DearVR Pro.
Take a squiz (and listen) to the video below. Be sure to wear headphones!