sfxr is a fantastic, free, and easy-to-use tool for creating 8-bit video game sound effects. Perfect for the game-writing students I teach, but I’m having a blast (ahem) with it, too.
Just pick your sound type (jump, shoot, power up, etc.) and listen to random permutations until you get something you like, or tweak the settings directly to get the exact sound you’re looking for.
Note that there’s a Mac port of it as well (cfxr), look for the link under the description.
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