Creating a *usable* Karplus-Strong effect within stock Renoise?

Sorry if this is in the wrong place. I figured this was too complex/specific a topic to put into the “beginner help” section, so I thought I’d put it here instead.

I like strings. I’d been using Famitracker for years, so when I first got Renoise about a month ago, I was really excited to use its extensive DAW features to more closely mimic the timbre of real-life instruments.

Recently I learned of the Karplus-Strong algorithm [https://en.wikipedia.org/wiki/Karplus–Strong_string_synthesis], which wikipedia describes as “using an inverted, scaled control system for very small time values in a filtered delay line to create playable notes”. Essentially, from what I understand, you apply a filtered delay to a tiny section of noise, and the timbre of a real string instrument is closely emulated.

Unfortunately, Renoise’s delay effect control isn’t granular enough for this to work. Each MS of delay accounts for several semitones, so if you stick a key tracker on it, it seems to almost work, but not very accurately. It’s almost usable. Is there any way to achieve this properly in the stock program? Am I missing something major here?

As you might be able to tell, the idea of “physical modeling” synthesis is still pretty new and alien to me. If anyone has any valuable resources, advice, tutorials, it would be much appreciated. The idea of using Renoise’s stock effects to achieve this kind of stuff seems pretty exciting to me.

You will not be able to get an advanced karplus strong with filter/feedback with renoise stock effect.

But you can get something similar, using a short noise burst or click into a renoise comb filter, that is tuned with a keytracker…

A comb filter is basically a short delay line. But there will be no filtering inside…

Have fun!

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