Interesting.  So it seems what he is doing is using the "string blade"
to vibrates just one string for the full range of the violin.  The
other two strings (this violin only has three strings) are selectively
played by the bow to add to the sound of the violin.  The pitch of
these two strings is controlled only by the speed of the bow.  The
pitch of the middle string is a combination of the bow speed and the
speed at which the computer vibrates the string blade to vibrate the
string.

In a nutshell, what is happening here is the violin is being forced to
a particular note by the computer vibrating to string blade.  If the
system is using only pure (no harmonic) waveforms to drive the middle
string (which I think it is) the instrument would sound flat.  Adding
the bow and the two other stings adds semi-natural harmonics to the
base sound so the instrument sounds more like a real violin.

Maybe it was just the MIDI file that they used, I don't know.  But
in listening to the violin play in the rather short video, it doesn't
sound bad; but it doesn't sound all that great either.  Although
I don't claim to be any kind of an authority on the finer points of
music and I'd like to hear one of these in person to form a more
informed opinion, this instrument is rather mechanical sounding.
It doesn't cross over between notes very well.  The instrument seems
always to have each note be separate and distinct.

A real violin has the ability play different notes one after another
as one continuos one tone.  A real violin has a subtle initial "skid
on the road" quality to each note where the bow reverses direction,
this instrument seems to lack much of that.  Also it seems to lack the
subtlety and variations that a human player on a real violin has.

It is like the difference between playing a quality classical piece
on a standard run of the mill player and a well maintained reproducing
piano.  While both will play the piece as faithfully as possible, however
side by side by, one will be a joy to hear while the other will be
disappointing.

Like I say, it doesn't sound bad.  But at $17500.00 I would have
expected, well, more.  In short, although it is very impressive, it
doesn't seem to have to the full richness of a real violin.  I don't
think the price justifies the less than natural sound.

My two cents,
Ray Finch
Albuquerque, New Mexico