SuperCollider Tutorial: 31. Ambisonics

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This video introduces Ambisonics, a family of techniques for rendering and manipulating immersive, spatial sound in three dimensions. These techniques are made possible by the Ambisonic Toolkit (ATK), distributed as a SuperCollider Quark, the development of which is led by Joseph Anderson, a composer and research scientist in the DXARTS program at the University of Washington. Special thanks to Jo, without whom this tutorial would not have been possible, and thanks to the entire team of artists and researchers who've contributed to this fantastic project.
0:00 Introduction
1:05 Fundamentals of Ambisonic Theory
8:13 Introducing the ATK
8:41 Installing the ATK
11:51 Basics of the ATK Workflow
12:50 A Visualization of Useful ATK Classes and Methods
17:32 Basic FOA Examples
19:17 Orienting Ourselves within the Soundfield
20:48 FOA Matrix-Based Examples
36:36 FOA Kernel-Based Examples (e.g. binaural and HRTF)
42:02 Decoding FOA for Multichannel and Surround Systems
46:07 Understanding Higher-Order Ambisonics
48:50 Basic HOA Examples
54:24 HOA/FOA Conversion & Understanding Encoding Formats
1:03:31 Other Ambisonic Conversion Scenarios
1:08:37 ATK Utility Classes: FoaXformDisplay
1:10:33 ATK Utility Classes: TDesign
1:12:31 Conclusions
Resources and related topics:
The ATK website: www.ambisonictoolkit.net/
The ATK on GitHub: github.com/ambisonictoolkit/
DXARTS at the University of Washington: dxarts.washington.edu/
Ambisonics on Wikipedia:
en.wikipedia.org/wiki/Ambisonics
en.wikipedia.org/wiki/Ambison...
en.wikipedia.org/wiki/List_of...
An excellent book on Ambisonics, written by Franz Zotter and Matthias Frank: library.oapen.org/handle/20.5...
Two historical resources on Michael Gerzon's pioneering work with Ambisonics in the 1960s and 1970s: intothesoundfield.music.ox.ac... | www.michaelgerzonphotos.org.u...
A paper on binaural sound synthesis by C. Phillip Brown and Richard O. Duda, which serves as the foundation for the 'newSpherical' pseudo-binaural decoder method: citeseerx.ist.psu.edu/documen...
Impulse responses and HRTF data from IRCAM, on which the 'newListen' binaural decoder method is based: recherche.ircam.fr/equipes/sal...
A paper on soundfield synthesis based on convolutional neural networks by Comanducci, Antonacci and Sarti: arxiv.org/pdf/2205.12872.pdf
The Soundfield Synthesis Toolbox: sfs.readthedocs.io/en/3.2/

[@mattshu]

I listen to a lot of youtube channels that have ambient/techno soundscapes that are hours long and I honestly thought I clicked on one of those by accident at first glance of the background image and title of this lmao. Glad I stumbled on this!!!

[@ElieNaulleau]

Very clear, thank you very much.

[@laika6340]

i’m here for it

[@agapizita]

thank you!

[@aleksdizhe]

Hello, Eli! Would be glad to hear your opinion on what books/sources would be best to start from to understand maths for further learning of DSP and all sound-related/audio programming stuff? (for a person having a high school-university entry maths level) Thank you in advance!!

[@elifieldsteel]

I’ve learned a lot from The Computer Music Tutorial (Roads) over the years, and a 2nd edition was recently published. It is a robust and comprehensive text that spares no detail.

[@aleksdizhe]

@@elifieldsteel thank you for your response!

[@sebastianvillalba3260]

Muy bueno!
Cuál sería la forma correcta de agregar reverberación?

[@elifieldsteel]

I don’t think there’s a singular “correct” way to add reverb to an Ambisonic signal. Correctness depends on context. There are different techniques you can experiment with, and figure out which one you think sounds best.
There is an AmbiVerbSC UGen. It’s a quark, built with the ATK in mind, but not included in the ATK quark distribution, so it needs to be downloaded and installed separately. I’ve briefly looked at it, but never actually used it. github.com/JamesWenlock/AmbiVerbSC
Alternatively, you could pass your signal through a stereo reverb effect, and encode it to B-format separately from the dry signal. You could then apply different soundfield transformations to the dry and wet signals, which might be interesting. You could also decode them differently.
You could also pass a B-format signal through a bank of monophonic reverberators, each with slightly different parameters, which could also have interesting results.
There are probably lots of other options.

[@sebastianvillalba3260]

Te agradezco muchísimo la respuesta. Voy a hacer todo eso.
Pero aprovecho para hacerte una consulta.
Estoy siguiendo el tutorial paso a paso, y cuando en el minuto 27 (aprox) cuando se agrega la FoaRotate, me sale un error, y quedé trabado ahí.
El error dice exactamente:
exception in GraphDef_Recv: UGen 'FoaRotate' not installed.
*** ERROR: SynthDef ambi not found
FAILURE IN SERVER /s_new SynthDef not found
Hace un par de horas que estoy con esto, inclusive desinstalé Supercollider por completo, borrando la carpeta del AppData (soy usuario de Windows), instalando sc3-plugins con Quarks, y atk-sc3 desde el zip. No lo puedo solucionar, y en internet no encuentro nada sobre el asunto.
Ya no sé que hacer, y no puedo avanzar.
No me figura que tenga error de instalación. Simplemente me dice eso, que FoaRotate no está instalado.

[@elifieldsteel]

@@sebastianvillalba3260 It's difficult to say with accuracy using only this information, but my guess is that you installed the ATK Quark correctly, but not the sc3-plugins package. You will need to install both to use the ATK. Maybe you copied the plugins to the wrong location? Or forgot to recompile the library? I found this thread, which seems to be the same problem you're experiencing, although with a different UGen from a different quark scsynth.org/t/installed-quark-plugin-not-found/5527. You could also post your question on scsynth.org, and I'm sure someone will quickly point you in the right direction.

[@sebastianvillalba3260]

@@elifieldsteel recién, después de 3 días, logré hacerlo. Y no se exactamente como lo logré... Lo cual es frustrante. Pero bienvenido sea.
Aprovecho para decirte que veo todos tus videos. Son obligatorios para consultas e inspiración. Te agradezco todo y te mando un abrazo desde Argentina!

[@PerplexedMuse]

🤍🤍🤍