Founder of the Abbey Road Spatial Audio Forum, Mirek Stiles, Visits the York AES 2019 Convention

8th April 2019
"Sinking further down the Spatial Audio rabbit hole, I spent 3 days at York University last week for the Audio Engineering Society International Conference on Immersive and Interactive Audio. I thought the conference title was a bit of a mouthful, but that was nothing compared to the sheer scale of diverse and thoroughly fascinating talks, demos and panel discussions from some of the most inspiring people in the business. It was a good place to be, if you are into that sort of thing. Here are some highlights."
 
 
"First up was a talk on the history of Ambisonics at York University by the legendary Dave Malham. I loved the images he showed of the original analogue gear they used back in the 70s – hand built sound field manipulation devices we now take for granted via the various plugins available to us. There were also early examples of Ambisonic software coded for the Atari ST format – it was all a bit nostalgic for me, as although I didn’t know what Ambisonics was back then I certainly remember the Atari being my first introduction to computer music software. To think the students and team at York Uni were pushing the boundaries of what the Atari could do to the absolute limit – recording 4 channels of digital audio simultaneously onto a home computer, something we take granted now but must have been pretty mind blowing at the time."
 
 
"I also witnessed a great talk by Simon Goodwin, who I think is pretty much one of the most knowledgeable game audio experts in the UK, who’s been developing since the days of the ZX Spectrum home computer. He was discussing in some detail things like setting up complex ambience zones within the game engine – things I’m still getting my head around. The talk gave me the impression this guy had seen it all and done it all with regards to game audio. The early limitations set upon the gaming world when it came to music and sound must seem laughable compared to the resources available today, but as with the music recording industry, those limitations required the artist to come up with imaginary solutions for their vision. I have had the pleasure of working with some of the most iconic names in music and film but it’s easy to forget every industry has these legends, and Simon is no exception. Simon has just released a book which I’ll be checking out."

"Early on day two I headed straight to the audio lab at the Uni to meet with Calum Armstrong who has a new method for capturing personalised HRTFs (Head related transfer function). This method is way quicker and more comfortable than the last time Calum did my ears – 90 mins sat on a bicycle seat in a cold anechoic chamber vs. the new 5 mins standing in a nice warm audio lab. I got to hear the results almost immediately in a blind listing test against 5 other HRTFs. One of the 6 HRTFs I selected in the blind test sounded by far the best over the rest, better imaging and frequency response, and I’m happy to say it was my one. His new measuring method seems to be incorporating a technique called Spherical harmonic HRTF’s, this seems to add some sort of spatial smoothing to the result (I’m most likely massively over-simplifying it with this feeble explanation). Whatever Calum is doing, it works! I was lucky to get mine done, this was completely over-subscribed, and I think the audio lab team had their work cut out for them over 3-day duration."
 
 
"Fellow Abbey Road Spatial Audio Forum member Dr Hyunkook Lee from the University of Huddersfield gave an impressive talk (they always are) about his findings in creating height information from a single pair of stereo speakers. Certain frequencies give the listener perceived positions, higher frequencies tend to give the impression of coming from above and lower frequencies the impression of coming from below. Add to this that a phantom centre image appears to be slightly elevated to the listener - this effect increases the further apart the speakers are, when using various psycho acoustic effects, this can start to trick the listener to hear sound from above when only two speakers are present. This is a gross simplification of Hyunkook presentation, but I hope you get the idea. Stephen Barton, Hyunkook and I had the opportunity later that day to listen to Stephen's latest game score we recorded in Studio One at Abbey Road on a 9.1 speaker array set up in the basement of the University. We decoded various microphone arrays we recorded on the session, including Hyunkook ESMA array and the Sennheiser Ambeo Cube to the 9.1 layout – it sounded pretty awesome!"
 
 
"Anastasia Devana, Audio Director for Magic Leap and fellow AR Forum member gave the closing day key note on the challenges of creating sound for AR/VR/XR. The main focus was getting across the fact that unlike film and TV, with VR/AR there is no director guiding the camera to where the audience is supposed to be looking and what they are supposed to be hearing. With VR and AR, the user is the camera. How we create sound design to compensate for this anomality is what can make or break an experience. With Augmented Reality things are complicated further by the fact virtual objects are being incorporated into real surroundings. With linear formats such as film or non-linear VR experiences, sound design just has to be believable and impressive, not necessarily realistic and that is fine. But for AR the sound coming from a virtual object in a real environment has to sound authentic, not only from the object itself but also the reverb of the room that object is triggering. If not, the illusion will be broken. I thought Anastasia's talk was very thought provoking and some excellent examples were provided to really back up these concerns. The workflow of sound design is well and truly evolving."
 
 
"Finally, it was with great pleasure the Abbey Road Spatial Audio Forum was invited to provide the closing panel discussion. Hosted by Dr Gavin Kearney from the University of York, myself, along with Anastasia from Magic Leap, game and film composer Stephen Barton, Executive Digital Producer Muki Kulhan and Dr Lorenzo Picinali from Imperial College London gave a lively little talk on content creation tools for immersive media, although I’m sure we wondered wildly off topic on several occasions. It was pretty much a typical Abbey Road Forum meeting but with a live studio audience and everything we said being committed to video forever - nice. As Anastasia and Stephen debated to pros and cons of Ambisonics for 6DOF, I couldn’t help but sit back a little and admire what a fantastic bunch of talented, enthusiastic and just generally fun people we have on the forum - the hour we had literally flew by. I’m grateful to Gavin and the AES for being our host and letting us say some words. Hopefully we will be allowed back again in the future."

"Overall, I would like to thank Dr Gavin Kearney for putting the event together, quite a big undertaking. I know he had an amazing team with him there from the University who all did their bit. It was such a great event. I had a lot of fun, met some new people and learnt some new stuff – you can’t really ask for much than that can you?"