[sdiy] Evelope Follower

[Tim Escobedo]

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The easiest envelope follower circuits can probably be found in guitar
pedals. These generally involve tapping into the original signal,
amplifying it, rectifying it, and filtering it. The result is a DC
voltage proportional to the level of the original signal. It's
particularly effective with dynamic signals like those from electric
guitar. With a rather static signal, whose envelope characteristics are
more on/off, the envelope follower may be less effective unless
preceded by a EG/VCA, or some kind of "attack" control is built in to
the env follower. 

http://www.muzique.com/schem/quack.gif has a simple example of an
envelope follower (IC1a).

--- Dr Strangelove <phdinfunk at hotmail.com> wrote:
> Hi, I've been working away trying to build a little mono-synth but
> the next
> semester is nearly upon me so I'm revising my plans.  I've got a
> working
> filter I've built that I like a lot and I like the way all sorts of
> sounds
> work with it.  I am wanting to place the filter in a crybaby wah-wah
> housing
> and have the cutoff under foot control, I also want to have an
> envelope
> follower in there too with variable control voltage sent to the
> filter
> cutoff.  I'll place the knobs for input level, Envelope follower
> control and
> resonance on the top of the crybaby.  It should be lots of fun.
>
> I cannot find a schematic for an envelope follower.  Can anyone
> direct me to
> a good envelope follower schematic, preferably a simple one?  I'm
> using +/-
> 12v power. :-)
>
>          -=<Jonathan Pratt>=-
>        (Phdinfunk at hotmail.com)
>
>
>
>
>
> _________________________________________________________________
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