[sdiy] PLL examples

[ChristianH]

On Fri, 6 Jan 2006 12:04:42 +0100 "JH." <jhaible at debitel.net> wrote:

> > Guitars are notorious for trashy output signals.  What really confuses a
> PLL
> > is the fact that a guitar signal can have more then 2 zero crossings per
> wave
> > cycle.
> 
> Zero crossings are more an indicator for formants than for the pitch of a
> signal.
> (At least I read that somewhere.)
> 
> As far as I can tell from a brief glance, that Boss circuit which was posted
> yesterday
> is looking for *peaks*, not zeroes. Looks very similar to the EMS method as
> used
> in the HiFli.
> 
> JH.



Wouldn't it be necessary to limit this to "real" peaks somehow?

Thinking of e.g. a low pass filtered square wave - formally, there are
lots of peaks due to ringing at each edge.

Christian