I’m learning the Tocante Karper, one of the latest in the line of Tocantes by Peter Blasser.   Here’s a demo video in which I show some of the playing technique I’ve discovered.  I don’t know the theory of its design.  This is an empirical investigation.  (I had it plugged into my Roland Mobile Cube amp.)

• Pitches start out similar to the other Tocantes when powered on.  But, each pad/oscillator can be changed to a random pitch, widely ranged.
• New pitches are held until power cycled or changed again.
• The random pitches are obtained by the inner two pads.  I don’t yet understand how the two pads work in relation to each other.
• Quickly striking the large pad produces a plucked sound that is strongly pitched.
• Holding the large pad produces a sound that seems to me like a guitar string stimulator, a centered pitch with a lot of activity.
• I didn’t demo the inner nodes.  As far as I can tell they inject noise.