[sdiy] New site for og2 DIY synth project

[Scott Bernardi]

The Vocoder pages aren't quite ready for prime time. This is more of a
research project than a "build it" project at this point. I've gone through
several iterations of what I would need for the filters, and finally have
settled on 3rd order staggered MFB bandpasses spaced at 1/3 octave (16 bands).

I wrote a cool Java applet that calculates the component values; you give it
the desired center frequency, Q and spread factor between the three poles, and
it picks appropriate standard cap values and calculates the necessary resistor
values.  You can override the cap values and it will recalculate the
resistors. Unfortunately, although the applet works fine in my Java IDE, it
doesn't work right just executed from a browser! I also made up a PCB that has
the 3 staggered MFB bandpass filters with DIP sockets to plug components in,
and DIP switches to isolate the stages for individual measurement, to test out
the practicality of my design - but it's not stuffed yet.
My schematics are also not up to date with my latest "experiments".
I don't like to put things up that haven't been at least breadboarded, so the
vocoder stuff will be a little while, because it's been taking a back seat to
og2.

mark verbos wrote:

> the vocoder link doesn't work. I would like to see that...
>
> Scott Bernardi wrote:
>
> > Well, I finally put up the new site for my og2 Synth project - I've only
> > been working on it for almost two years now (the synth, not the
> > website).
> > I've got the majority of my modules built and working, but I still don't
> > have an instrument to play yet! og2 will be a semi-modular with
> > overidable patches, and I've got a bunch of working PCB's, but haven't
> > built the front panel and case yet.
> > There are a lot of schematics presented. Some using CEM and SSM chips I
> > cannibalized out of my original OGEE synth built back in the 80's, but
> > also a lot of "from scratch" modules too. There's also a nice list of US
> > sources for parts.
> >
> > Check it out at
> > http://members.home.net/sbernardi/elec/og2/og2_home.html
> >
> > --
> > Scott Bernardi
> > sbernardi at home.net
>
> --
> mark verbos
>
> "if you want something done right, build it yourself."
>
> www.simple-answer.com
>
> watch out for...
> on my label SIMPLE ANSWER "White Enamel" Simple Answer 005 out now,
> distributed by Integrale, UK

--
Scott Bernardi
sbernardi at home.net