[sdiy] lots of VCAs on one PCB

[Kyle Stephens]

Joergen Bergfors did a "VCA Shootout" page, that gives a few options for VCAs and other performance figures.

http://hem.bredband.net/bersyn/VCA/vca_shootout.htm

Arguably if you went SMT you could do nigh whatever you wanted, though if you want to stick with through hole, this looks to be the smallest area with best performance:

http://hem.bredband.net/bersyn/VCA/ssm2024%20vca.htm

Per one set of SSM2044 and TL074 = 4 VCAs, with only 4 resistors and one cap per VCA. Even with power connectors and bypass caps, that's still pretty small.


_Kyle

--- On Mon, 11/23/09, Derek Holzer <derek at umatic.nl> wrote:

> From: Derek Holzer <derek at umatic.nl>
> Subject: [sdiy] lots of VCAs on one PCB
> To: "synthdiy DIY" <synth-diy at dropmix.xs4all.nl>
> Cc: "Derek Holzer" <derek at umatic.nl>
> Date: Monday, November 23, 2009, 4:13 PM
> Howdy all,
> 
> I'm looking at building a joystick controlled 4x4 matrix
> mixer, which requires 16 VCAs when it's all added up. It
> would be for control voltage, so a linear VCA is required.
> I've looked at the Thomas Henry VCA, which is pretty simple
> and quite nice, but all the layouts I've found for it are
> fairly large.
> 
> It struck me that a vocoder would need approximately the
> same amount of VCAs (depending on the number of
> analysis/resynthesis channels of course), so there must be
> some layout someplace that has a lot of VCAs packed together
> on one PCB board.
> 
> Can anyone point me to a layout that packs so much into a
> fairly small space (one Eurocard sized PCB 100x120mm)? Or a
> super basic linear VCA schemo that could be laid out in such
> a way? Alternately, is there anyone interested in working
> with me to design such a thing? I'd be willing to invest
> something in getting PCBs made in this case.
> 
> Best!
> Derek
> 
> --::: derek holzer ::: http://blog.myspace.com/macumbista ::: http://www.vimeo.com/macumbista :::
> ---Oblique Strategy # 118:
> "Make what's perfect more human"
> 
> 
> 
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at dropmix.xs4all.nl
> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>