This is really interesting and simple simulation of plucked string. You can read about it on Wikipedia – Karplus-Strong. I've found this explanation when I had it half implemented, it's really good.

Here's the diagram of feedback loop (source):

The delay line is initialised by white noise (length of the line is determined by frequency).

Examples:

The last one sounds good but is not clear because I've done some tweaking. It can sound even better, but I don't know how (yet). I've been trying to implement the extended algorithm but I don't understand the theory enough to know what I'm doing wrong.

Dependencies:

• python-tksnack which depends on libsnack2 (install libsnack2-alsa or you may be surprised by loud output at midnight)

tkSnack depends on Tkinter which is part of Python library so I used it for GUI too.

Download:

• sources