[sdiy] favorite adsr?

[Dave Kendall]

I don't know if it's typical, but the EFM VCRADSR uses a LM3080 and 
CD4052, and is quite a compact design.
http://www.modular.fonik.de/files/EFMforum/orgEFMfiles/vcradsr.pdf

With a small amount of resistor/cap value tweaking and a couple of mods 
(a re-trigger input, and comparators on the gate and re-trigger inputs) 
it works very well, and can operate as a LFO too. Looks like it could 
be easily updated to use the LM13700.

cheers,
Dave

On May 29, 2009, at 22:38, David G. Dixon wrote:

> Here's a general question regarding VC-ADSR:  How is the voltage 
> control
> accomplished, typically?   Is it through the use of an OTA or similar
> voltage/current-controlled gain block as a variable resistor for 
> defining
> the A, D and R time constants?
>
> In that case, it would seem like an SSM2164 would be an ideal choice 
> for
> making an analogue VC-ADSR with a relatively small parts count.  
> Indeed, by
> my reckoning, this would add about 1 square inch of board space to a
> conventional ADSR with (only) manual timing control.
>
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