stupid envelope follower idea

[Don Tillman]

   Date: Tue, 21 Nov 2000 16:45:22 +0100 (MET)
   From: Martin Czech <czech at Micronas.Com>

   Envelope followers all suffer from the ripple/speed tradeoff.

Nahhhh, not if you're clever.  

It's a simple matter to split the input signal into several bands,
perform a separate envelope detection on each, and sum the results.
That way each frequency band can be optimized and you can have both
low ripple and high speed.

You can also use more exotic s/h-style peak detectors.

   Now, could it be improved via modulation techniques?

   I mean if I modulate the audio with some sine carrier,
   it would at least cut down the low frequency sideband by 1/2.
   If that is rectified and filtered, I think it would perform better.
   Like AM demodulation, well almost, but without carrier
   feedtrough.

I'm not getting this; how exactly would AM modulation help?

  -- Don

-- 
Don Tillman
Palo Alto, California, USA
don at till.com
http://www.till.com