Linear VCF

[Tim Ressel]

This is why I want a linear ADSR: otherwise you get the "double expo" effect on
any expo input you use. I'm down to a few wires on the prototype; perhaps this
weekend I can start banging out some code (yes, it uses a dredded uP)

--Timster (with WAY too many irons in the fire; my brain goes faster than my
hands)

Tim Ressel--Compliance Engineer
Hewlett-Packard
Verifone Division
916-630-2541  
tim_r1 at verifone.com                     



-----Original Message-----
From: Tony Allgood [mailto:oakley at techrepairs.freeserve.co.uk]
Sent: Thursday, June 22, 2000 2:33 PM
To: Synth DIY
Subject: Linear VCF


Hi all,

All this talk of expo inputs on LFOs reminds me to say that I have been
chuffed to bits with the linear modulation inputs on my new filters. Do
try it on your own designs if you can.

We have all got used to the 'double' expo effect on VCFs when sweeping
the VCF with a standard ADSR. Since our EGs are exponential, in most
cases, most of us use linear VCAs. Expo VCAs are used when we want a
really percussive sort of thing. But our VCFs are almost invariably expo
anyway. So we will always get a 'percussive' sweep. Using the linear
input seems to result in more natural decays, softer sounds even if the
sweep amplitude is big.


Regards,

Tony Allgood  Penrith, Cumbria, UK

Modular synth circuits, TB303 clone and Filter Rack

http://www.techrepairs.freeserve.co.uk/projects.htm