Press the Speaker to play the currently loaded WAV (The project has a default already loaded) (Wait for progress to reach 100%) "Pitch" and "Speed" Make the sound higher pitched and faster independently, something not usually possible in Scratch This project uses additive synthesis, and as such stores 1024 different sound effects. It might take time to load. Press space to load a new WAV: The file must be Mono, 16 Bit PCM Uncompressed, with a Sample rate of 8000 Hz The file then must be converted to hex here: https://tomeko.net/online_tools/file_to_hex.php?lang=en , where insert newlines and separators are unchecked An easy way to this is to go to this site: https://www.freeconvert.com/mp3-to-wav , Find "Audio Options", and set "Audio Codec" to "PCM_S16LE (16 bit, Uncompressed)", "Audio Sample Rate" to "8000 Hz", and "Audio Channels" to "Mono", then just import an MP3 Why I think the audio quality is bad: This project relies on synced sine/cosine sound waves that become desynced over time due to how Scratch manages multiple threads, losing a property known as "phase"
FFT Algorithm is a slightly modified version of what @Kouzeru uses: https://scratch.mit.edu/projects/470900402/