Shitwave – A PRNG based drone generator for Gameboy

Little-scale recently posted All 4-bit Waveforms That Have 32 Samples, a Max patch that would generate all possible wave frames that could be used with LSDj, given gazillions years. However, the result was a little boring because it would start out as a 1/32 PWM and slowly progress towards a longer and longer PWM. Even within many years, chances are you’d still have a very low duty PWM.

So I decided to find an algorithm that would produce more interesting sounds and still cycle through all 1632 possibilities. My choice was a Pseudo Random Number Generator using a Linear Feedback Shift Register. Actually not completely unlike the one in the Gameboy’s noise generator.

However, where the GB’s generator goes through a small number of states, and the buffer constitutes one sample, I’m using the full 16 bytes (32 samples) used in the Gameboy’s wave channel as my shift register. (Equivalent of one frame in the LSDj softsynth)

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