Beginner question on writing a wavetable synth

[ch0ronomato]

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Hi!

I'm a software engineer by trade and have recently started writing a wavetable synth as a hobby project in rust. I was hoping to get some help / guidance on any misunderstandings I might be having. The code is here https://github.com/Ch0ronomato/wavetabl ... dfdd2209b8 (https://github.com/Ch0ronomato/wavetablers/commit/cf4bb0b584163be1a27f7dfe5c8888dfdd2209b8)

I was attempting to try to "embed" a square wave into my code, but only using 0 and 1 in this case (non-fouier) because I want to understand why we would need to to use fourier series instead. This code does work, it produces a pretty harsh sound at roughly 440hz, but I'm still confused on some things. I felt like this site https://www.music.mcgill.ca/~gary/307/w ... ables.html (https://www.music.mcgill.ca/~gary/307/week4/wavetables.html) helped describe some of the terms, but I'm still confused.

When you take some wave stored in a wavetable, and you want to produce that sound at a pitch, are you essentially going through the wavetable at a certain iteration speed? (That's how I understood this article). If so, how does this change when you're doing multiple notes?

Sorry if it's newby

[imrae]

For a polyphonic instrument you will need to run multiple “voices” in parallel, each looking up wavetable values using their own phase information, and mix them together. (They will also need their own envelope/VCA unless you are going paraphonic...)

[BertKoor]

We have a DSP & Plugin development section here. You can search for wavetable there, it returns 12 pages with threads. Some of them contain true gems. Read some...

I want to understand why we would need to to use fourier series instead.

You want to exclude all frequencies above Nyquist because these are the cause of aliasing. Here's a pretty decent explanation of the aliasing phenomena:



And a demonstration on square waves aliasing: