Convert solo voice to choir

i don't know if it'll REALLY sound like a choir, but sure, duplicate the track 19 times, copy and then paste the region into the 19 new tracks, do the pasting sloppily so that they don't all start at the same exact time, then add different effects to every track (pitch shifting would likely be one of the important effects)

to get it slightly better i'd suggest singing it 10 or 20 times so that many tracks really are slightly different right off.

I think the recording multiple tracks is probably better.

I've found that when I've duplicated a vocal Track and Region and shifted it slightly, that it just gave it an echo effect (which I can achieve with the Echo effect). Is there something else that should be done?

antares makes some pricey plug-ins, but from what i've read they are good.

i'd still be willing to bet that with enough time and patience, you could do a decent approximation of what they're doing with a combination of effects apple's provided.

pitch shifting, flanging, anything, really, just make every track subtly different (panning would be important too)