[sdiy] Small and simple vca details desired (oh, and a voltage invertor too)

[Ray Wilson]

Thanks for the feedback and suggestions Harry. I'll definitely give that a 
shot.

Ray

----- Original Message ----- 
From: "Harry Bissell Jr" <harrybissell at prodigy.net>
To: <raywilson at comcast.net>; <synth at oldmail.charlielamm.com>; "Julian" 
<julian at 22host24.com>
Cc: "Synth DIY" <synth-diy at dropmix.xs4all.nl>
Sent: Wednesday, March 02, 2005 4:16 PM
Subject: Re: [sdiy] Small and simple vca details desired (oh, and a voltage 
invertor too)


> Hi Ray...
>
> you might want to try adding a 15K resistor to the +15
> and the linearizing diode terminal, and add a divider
> and DC offset pot to the unused input terminal. Make
> the input divider like a 30K : 1K.  This will make the
> input signal red hot, and the linearizing diodes will
> allow the signal through without distortion.
>
> Downside... lower input impedance, and the need to use
> the DC offset adjust. You 'might' like the soft
> clipping of the circuit you have now...
>
> Upside, lower noise and distortion
>
> H^) harry
>
>
> --- raywilson at comcast.net wrote:
>
>> Check out
>>
>>
> http://www.musicfromouterspace.com/analogsynth/vca.html
>>
>> Its small and simple.
>>
>> Ray
>> -------------- Original message -------------- 
>>
>> > Not stripboard, but easy and reasonably low parts
>> count....You could try
>> > the "irwin dual VCA" I have details and PCB's for
>> it on my site.
>> >
>> > http://www.charlielamm.com/synth/duallinearvca.php
>>
>> >
>> >
>> > On Wed, 2 Mar 2005, Julian wrote:
>> >
>> > > Hello,
>> > >
>> > > I want to build a vca bank. No pots, just each
>> vca having 4 jacks - in and
>> > out, and 2 CV controls. Rather like doepfers a-132
>>
>> > > dualvca, but i plan to have more then dual.
>> > >
>> > > Im pretty rubbish at building on stipboard, so
>> the component count has to be
>> > low.
>> > >
>> > > Yeah, i know google will turf up 50k, but i was
>> wanting a recommendation?
>> > >
>> > > Cheers, Julian
>> > >
>> > > ps. im trying to replace the utility modules in
>> my commercial modular with
>> > diy stuff. ken stone does mixer pcbs real cheap,
>> so ill
>> > > get some of them, but voltage invertors... (?)
>> > >
>> > >
>> > >
>> >
>