[DECtalk] DecTalk newbie

[Cary]

Hey guys, I'm a DecTalk newbie.  I downloaded the DecTalk demo and I've been
fooling around with the ability to make DecTalk sing.  What I want to know
is if there is a way to make DecTalk harmonize with itself.  I know this can
be done because there are dozens of files out there that have DecTalk
harmonizing with itself, but  what I'm wondering is if the people that did
it used some sort of wave recording software to make it happen.  If so, I'm
not much of a sound engineer, so I don't know how to do all that nifty
stuff.  But I definitely can make DecTalk sound relatively decent, just
based on the manual and the tutorial on Shwatskoff's site, not sure if I
spelled his name right, sorry if I didn't. heh
So basically, I'm wondering how to make DecTalk harmonize with itself,
without the use of nifty cool recording software.  If there isn't a way, I
guess I'm SOL. heh
-Cary