[sdiy] Fast envelope follower circuit needed..

[Richie Burnett]

Hi all,

A few weeks back I posted a response here recommending the OP to investigate 
using the Hilbert Transform to extract the envelope from a signal.  This was 
because I've had good results using this in some specific DSP products. 
However, Bernie Hutchins initiated some interesting off-list discussions 
about this, and he has pointed out to me several example situations where 
this method does not yield the envelope that a synth enthusiast might 
intuitively expect to see!

I don't want to go into this in too much depth because the thread didn't get 
much response anyway, and Bernie has looked into this in far more depth than 
I did, some years previously.  He has kindly agreed to me including a link 
to his thorough analysis here:

http://electronotes.netfirms.com/AN355.pdf

My appologies for any confusion caused.

Best regards,

-Richie,