The Amiga has got four 8-bit sample playback channels. To get noise out of it, you point each channel to a bit of RAM, tell it how big it is and that's what it plays. If it's a big long sample, it will play a big long sample. If it's a tiny 64-byte piece of data, it will loop it, making it sound like a continuous tone. "chip" tunes are just little looping blocks of data. For the 4k demos, it would be more efficient to write a tiny piece of code that would generate a waveform mathematically in RAM.
Last edited by FromWithin; 14 August 2003 at 13:50.