[sdiy] CV-vactrol circuit

Richie Burnett rburnett at richieburnett.co.uk
Sat Jul 4 01:18:30 CEST 2015

Digital pots sound like a better idea to me.  If you add a low-end 
micro-controller you can have the choice of either CV control or MIDI 


-----Original Message----- 
From: Gordonjcp
Sent: Friday, July 03, 2015 11:46 PM
To: synth-diy at dropmix.xs4all.nl
Subject: Re: [sdiy] CV-vactrol circuit

On Fri, Jul 03, 2015 at 08:58:51PM +0000, niroke at tampabay.rr.com wrote:
> I'm trying to add external control to my TR-9090's voice parameters, and 
> I'm sure if that was as simple as patching in to a CV summing point, it 
> would have been done by now.  The 909 circuits don't lend themselves to 
> voltage control.  From what I know, I can control the parameters with a 
> vactrol in series with the variable resistor.  If you have a better 
> solution, I'm eager to hear it!

You could try digital pots, maybe?  Does it *have* to be a control voltage?

Gordonjcp MM0YEQ

Synth-diy mailing list
Synth-diy at dropmix.xs4all.nl

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2014.0.4813 / Virus Database: 4365/10155 - Release Date: 07/03/15 

More information about the Synth-diy mailing list