Understanding how sound works is central to being better at working with it. Sound is often described as having three principal characteristics: amplitude, pitch and timbre, and if we dig deeper we find that all three of those are intrinsically linked. All complexity in sound is a result of combining more and more simple sounds on top of each other and it’s because of this, and some really clever maths that so many of the processes which, back in the analogue days simply weren’t possible are now commonplace.
We have two videos which illustrate this point beautifully. The first demonstrates in a thorough, but brilliantly lighthearted way, the fact that by adding simple tones together you can create any sound at all - Every sound is sine…
As alluded to in the video above, some of the digital processes which back in the analogue days would have been considered impossible are actually just a result of clever people using powerful computers and really clever maths to exploit the fact that complex sounds can be reverse engineered back into their constituent parts. This is the audio equivalent of un-mixing different colours of paint from each other.
Fourier Analysis - Build A ‘Frequency Unmixing Machine’
Everything from spectrum analysers, to tuning software, unmixing software and noise reduction rely on the ability to be able to extract information about complex sounds and the most powerful tool for this is Fourier analysis. Most people involved in audio have heard of this but rather fewer know how it actually works. There is some pretty complex maths involved here but this second video is really accessible, particularly because it uses graphics so well to illustrate how complex waves can be broken out into their simple, sine elements and even recombined back into their original form. It gets complex but the first half of the video is really accessible and if you’ve ever wondered how you can unmix sounds, this is highly recommended.