re-re-re percussion ribbon...Addendum

Grant Richter grichter at
Thu Nov 18 01:15:03 CET 1999

Just speaking of X-Y controllers, but without
percussion sensors.

There were a number of drawing pads for 8 bit
computers that could be modified to do this.
One designed for the Commodore 64 was very large
(12 inch x 12 inch) and had the advantage that
more than one "pixel" which means a point of
contact could be scanned in. 

That way you could measure applied force by
counting the number of contact points in a
location. Since object flatten with increased force
the area of the contact point increases with

The Atari and Kohala units used a voltage sensing
system and could only detect one point of contact.
However it would be easy to make an interface that
would output two voltages from an Atari drawing pad.

Bob Moogs Big Briar also made an X-Y controller
pad during the 80s (Model 300 I think)

The Korg Kaoss pad also has a pulsed signal that
could be sampled with two sample and holds to give
0 to 5 volt X and Y voltages.

I could dig out more information if people are interested.

> From: Scibona, Joe <joe.scibona at>
> To: 'synth-diy at'
> Subject: re-re-re percussion ribbon...Addendum
> Date: Wednesday, November 17, 1999 3:49 PM
> A couple more things I meant to include in my post on this.
> 1.  In addition to X-Y position info.,  this controller can be programmed
> act as multiple zones or pads.  Each with  its own function be that
> or control related. (like a mini drum set made up from what ever sounds
> like - for example... think of a bunch of velocity sensitive softkeys you
> can program)
> 2. The piezo sensor on the backing plate would give you trigger and
> Amplitude information.  Not just trigger. (also note the positioning of
> for optimum performance might be a little tricky to avoid over or underly
> sensitive spots)   
> (we all know how to sample and hold and threshold detect....don't we?)
> Joe

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