This describes band-limited sound synthesis, why it’s necessary, and an efficient implementation for simple waveforms like a square wave. It has been used in several video game console sound chip emulators. These clips demonstrate the sound quality:
- Zelda: Oracle of Ages on Nintendo Game Boy emulator
- Defenders of Oasis on Sega Master System emulator
- Blaster Master on Nintendo NES emulator
- More samples generated using algorithm
Contents
- Sampling a Waveform
- Square Wave
- The Nyquist Limit
- Square Wave Harmonics
- Band-Limited Synthesis
- Band-Limited Step
- Adding Band-Limited Steps
- First Difference
- Adding Differences
- Adding Band-Limited Step Differences
- Implementation
- Linear Interpolation Compared
References to digital signal processing material and source code
bandlimited.zip contains a simple C++ implementation of algorithm