[sdiy] Philip Gallo Lin/Expo SSM2164 VCA design

[Tom Wiltshire]

Thanks everyone. I'd only found:

http://www.geocities.com/gallomagnetix/mgbvca.html

which is a dead link.

To answer your question Neil, I was thinking "both at the same time". There were some CEM/SSM chips that did this, but it's possible (perhaps even "likely") that they used two separate VCAs internally. Also some of the VCAs in the Roland VCF/VCA chips - IRwhatever.

T.

On 9 Jan 2011, at 22:01, Neil Johnson wrote:

> Hi Tom,
> 
>> Secondly, are there published designs that use the SSM2164 to create a VCA with *both* lin and expo CV inputs? If not, I think we should get busy and make one!
> 
> Google shows:
> 
> http://www.sdiy.org/philgallo/mgbvca.html
> 
> http://www.emulatorarchive.com/Amplifiers/AM8164/am8164.html
> 
> http://m.bareille.free.fr/modular1/quadvca/quadvca.htm
> 
> When you say "..*both*.." do you mean "at the same time", or do you mean "can select either/or".
> 
> The ones above all have switchable lin/expo, so you can't have lin and expo at the same time.
> 
> Cheers,
> Neil
> --
> http://www.njohnson.co.uk
> 
> 
>