SynthModules

I like your idea of software modeling.  At one time I wrote code (a 
long time ago) that emulated a flywheel on a simple encoder.  Should 
be fun in Basic.

It seems silly to encode the ribbon to midi only to convert it back 
to cv's again.  I did some reverse-engineering on the Kurzweil 
ribbon.  It turns out it is three independant ribbons, each covering 
1/3 of the total.  Their software implementation stitches these 
sections back together for a continuous single ribbon.  I did an 
analog design that would offset and add these sections together and 
it got a bit more complicated than I wanted to wire up.  However, it 
would work great if you wanted three independant ribbons.

Dave

--- In SynthModules@yahoogroups.com, "grantrichter2001" 
<grichter@a...> wrote:
> > I also have a Kurzweil ribbon controller and want to write the
> > program to convert that midi stream to cvs.  I haven't gotten to 
> that
> > yet.
> 
> Actually, this is an interesting problem. MIDI continuous 
> controllers (CC) are only 7 bits (128 levels) and produce very 
> apparent zipper noise. You can use an analog slew unit on the 
> output to do a hardware interpolation.
> 
> More difficult but more interesting would be a software solution. 
> One possibility to is to use physical modelling. Model a mass 
> which is "pushed" by the course 7 bit steps and "coasts" to a 12 
> bit position. The amount of coasting is determined CC rate, or 
> the time interval between CC packet reception.
> 
> Another mental model would be a stepping motor with 128 steps 
> connected by a rubber shaft to an actual pot. In this model the 
> coarse 7 bit steps are connected with 12 bit line segments. But 
> there may not be enough processing time available and the line 
> slope needs to change with CC time interval to make a smooth 
> curve.
> 
> Then again, you could just hack an output jack into the Kurzweil 
> and pick up the output of the buffer for the linear force sensing 
> resistor (the rubber strip).