Binaural Audio & Psychoacoustics Explained (What is "8D" music and how is it created?)

What is "8D" Audio? (and creating our own) [Binaural Audio & Psychoacoustics]

In this video I explain so called "8D" audio nonsense I have seen popping up all around YouTube. What is it? How is it made? Can we use a similar technique for more interesting results? Can we make our own virtual binaural recordings? This and more, answered in this video!

I go over a demo, as well as break down what is actually happening in those videos. I then explore software used to create such effects, and then explore how similar software can be used with multitrack recordings. Sit back and enjoy!


Links and bonus information!

SoundScape Renderer

SoundScapeRenderer is the software I used for the binaural reproduction. SSR can generate binaural from an impulse using a convolution. It also has many aother modes for synthesis I didn't touch on in this video and can be used in real time, or with head tracking, etc.
Homepage: http://spatialaudio.net/ssr/
Documentation: https://ssr.readthedocs.io/en/0.5.0/g...


What is impulse and convolution?

Take MATH213 or SE380 to find out! JK, convolution is like the combination of 2 signals (multiplication in Laplace domain for those who know) and an impulse is a type of sample just like a step (y=1) or ramp (y=x). An impulse is a loud, quick input, so you can see how something like the human ear behaves. Impulse recordings are also frequently used in reverb effects. If you record an impulse response, you can make any audio sound like it!
https://en.wikipedia.org/wiki/Convolu...
https://en.wikipedia.org/wiki/Impulse...


Binaural recording
https://en.wikipedia.org/wiki/Binaura...


Psychoacoustics
https://en.wikipedia.org/w/index.php?...


What is multitrack recording?

I showed some multitrack songs in this video. Multitrack recording started when you could record multiple channels or 'tracks' on the same tape. For example, stereo is 2 channels, but when recording, you would have a separate track for each instrument, etc - within the limits of how many tracks there are on the tape.


Multitrack samples

I did my initial experiments using the following free multitrack files.
https://www.cambridge-mt.com/ms/mtk/

It's a great resource to experiment with mixing music in Ardour as well! Huge props to the Cambridge Music Technology team for posting these!
Note that for use with SSR, I had to use SOX to resample these tracks into 48 kHz, and FFmpeg to merge the individual wav files into a single file, as I showed in the video.


SoX

I made use of SoX in this video. It's basically one of the trifecta of Linux multimedia tools, referred to as the "Swiss Army knife of sound processing programs" on their website. SoX stands for Sound eXchange for the curious.
Audio: SoX. Video: FFmpeg. Images: ImageMagick. These 3 programs have single-handedly done almost anything I need from them. SoX supports almost all codecs and has many filters and effects, LADSPA support, etc.
Homepage: http://sox.sourceforge.net/
Features: http://sox.sourceforge.net/Docs/Features


FFmpeg

I've spoken about FFmpeg in the past but it's great for any multimedia work!
Homepage: https://ffmpeg.org/
Filters (and amerge): https://ffmpeg.org/ffmpeg-filters.htm...

I figured out this technique of combining channels thanks to this guide on their site:
https://trac.ffmpeg.org/wiki/AudioCha...


JACK and Pipewire

JACK: https://jackaudio.org/
Pipewire: https://pipewire.org/ Really you should just use Pipewire with the Jack dropin!

What is Pipewire and Jack? Well, I made an entire video on this subject!
Linux Audio Explained:    • Linux Audio Explained (ALSA vs PulseA...  


Notes:
This video is not monetized, and any music samples used are strictly for educational purposes. I have no commercial intent, I just wanted to demonstrate interesting technology.
Song used at the start for my demonstration is Time Lapse by TheFatRat, available on YouTube.

Some comments on the setup with Jack are slightly out of date (this was filmed before the Linux audio video), and so SSR can now we run with Pipewire.

I love the making videos side of this channel, I hate the marketing part (hence why you don't get clickbait or fancy thumbnails or titles) hence the delays.

Any opinions or views presented in this video are my own and don't necessarily reflect the views and opinions of my employers.

Thanks for watching! I hope you enjoyed this and learned something!
Tony Tascioglu [2022]
https://wiki.tonytascioglu.com


(Any future corrections will be added here)