Karplus-Strong String Synthesis

[Inventor]

I recently learned about the Karplus-Strong string synthesis method which does a very good job at simulating stringed instruments such as guitars. Here is the Wikipedia page on it:

http://en.wikipedia.org/wiki/Karplus-Strong_string_synthesis

Just one quick glance at the illustration shows how simple it is. You send a short burst of noise (or practically any fast changing signal) into a summing amp, then feed the output back through a delay line and a filter to the summing amp. Very simple.

I've attached the ChucK program that I wrote which does a pretty good job of sounding like a guitar using this famous method.

Now, that's pretty much an analog circuit, and I don't know how much analog is considered kosher for Lunettas, but I wonder if a digital version would do a good job as well. The input noise burst can easily be replaced with a fast-changing square wave. The summing amp could be replaced with a two-input AND or OR gate (I think AND would be appropriate). The delay line could be some clocked D flip-flops, and the filter could be well, um, an RC filter.

I don't know, I'm just thinking out loud here... Suggestions or comments?

---

Digitar15.ck
Description:	A ChucK version of Karplus Strong complete with Boolean Sequencer and Monome-like keyboard interface	Download (listen)
Filename:	Digitar15.ck
Filesize:	15.01 KB
Downloaded:	497 Time(s)

---