[sdiy] V/Oct > V/Hz

[Magnus Danielson]

From: <dreichert at sympatico.ca>
Subject: Re: [sdiy] V/Oct > V/Hz
Date: Thu, 25 Sep 2003 18:18:32 -0400

> Hi Steve,
> 
> Check out pretty much any VCO design on the many webpages the members have
> here and simply build the exponential converter portion of them, then send
> the MIDI/CV through that and then into your synth.
> 
> I recommend the ASM-1 as a good one to use (though many other are very
> similar)
> 
> One key thing though is that most expo converters have a current output
> instead of voltage, and that they draw current instead of supplying it. The
> solution is to run the output through a simple unity gain inverting
> amplifier.

To make things simpler, I offer a little schematic of a V/oct to Hz/V
converter. You will find it amongst other things at:

http://home.swipnet.se/cfmd/synths/schematics/

It is the expo-section from the ASM-1 VCO ripped out and with a I/V-converter.

Enjoy!

Cheers,
Magnus