6 gig Music Maker + 6 gig Soundpool + 6 gig Soundpool 18 = 18 gig which is a big slice of 120 gig C drive - especially considering I have 2 terabytes on other drives. At least I can move 12 gig elsewhere.
Yes you can. In fact it's a very good idea. That way you'll have TWO hard drives that can work independently at the same time, which will decrease your access time and make the program run smoother. If it was all on one hard drive, it would have to run the program AND try to read media files at the same time - not a good situation.
The only issue is that when you copy/move the media files to another drive, you will need to clear the soundpools and reload them from their new location. Not a big deal, but something you need to know.