Ambisonics Final Year Project (2010) – A Summary
Seeing as I posted the interim report for my final year project here (in March last year), I think it’s probably worthwhile me talking about the final results. Whilst I won’t be posting the complete code listing for my plug-in yet, I presented a poster at an IET event last year giving an overview, a copy of which is below:
IET Presentation Poster - Ambisonic Surround
If that sounds useful, email me and I’ll be happy to chat a bit more about it – I have a riveting 120 page report that I’ll be glad to let people read on demand (!). Admittedly it’s been a while ago now, and I’m not currently developing it any further, but I’m still proud of what I managed to produce over those 9 months and may well re-visit my work if anyone expresses an interest!
By the time I submitted the project, I had achieved more than what I set out to initially. The software developed (a large part of the project) was a VST plug-in that synthesised periphonic room acoustics (reverb) based on a number of input parameters (room dimensions, surface material, source/listener position) and a number of system parameters. Basically, a clever type of echo generator for music producers and broadcasters. It had pretty convincing results, although I was constrained a little by the size and simplicity of the speaker array I was using to test it.
Physical modelling algorithms like the ones I used to create my reverb need a compromise between computation power and accuracy; passable results can be achieved using relatively small amounts of processing, but really convincing results need a bit more CPU power. I also developed some ambisonic decoding hardware, but it was a very basic design and wasn’t quite so interesting (read a bit here).
Ambisonics is a really interesting concept – a surround sound technology developed in the ’70s but apparently killed off by bad marketing and bad luck. Hopefully, with the benefit of cheap, powerful modern computers, it’ll resurface a bit more. There’s a blog here, for instance, where the BBC talk about using it for archiving surround sound broadcasts.
