[CM] portamento

[bil at ccrma.Stanford.EDU]

I think in the context of sound synthesis, portamento
is a glissando between two notes.  It would be interesting
to get a vocal or violin recording of someone using
portamento, and try to imitate it -- I think you'll
also need an amplitude envelope.  Seashore wrote about
it, saying something like "it starts below the first
note and overshoots its target", if I remember right.
You might also need to change the timbre en route.