Pages tagged dsp:

The DFT “à Pied”: Mastering The Fourier Transform in One Day - The DSP Dimension
Recreating the THX Deep Note - EarSlap

<blockquote> <p>So let’s get going. SuperCollider is my tool of choice here. I start with a simple waveform. I want to use a sawtooth wave as the oscillator source, it has a rich and harmonic spectrum consisting of even and odd partials. I’ll want to filter the upper partials later on. Here is some beginning code:</p> <pre> //30 oscillators together, distributed across the stereo field ( { var numVoices = 30; //generating initial random fundamentals: var fundamentals = {rrand(200.0, 400.0)}!numVoices; Mix ({|numTone| var freq = fundamentals[numTone]; (, rrand(-0.5, 0.5), //stereo placement of voices numVoices.reciprocal //scale the amplitude of each voice ) }!numVoices); }.play; ) </pre> </blockquote>
If you’ve ever watched a movie in a movie theater, chances are that you are familiar with the “Deep Note”, the audio logo of THX. That sound is one of the first sounds we hear at the beginning of movie trailers in a THX-certified venue. The origins of that sound tickled my curiosity and I did some little research. I’m deeply moved by the history behind it, and I want to share what I’ve learned with you. Then we will move on to create that sound ourselves, get your scissors ready, and some glue!
Music and Computers, Table of Contents
Free online book with great explanations of some very sophisticated concepts in the world of digital audio.
Music and Computers
nice intro to computer music and audio