I'm stalling something that is 97gb, but it's taking up over 300gb, why?

I have a new PC, I am a musician and I am loading all my music software on to my new PC.  I have a 1TB hard drive and my music files are 97gb.  I've been installing my sounds over night as there's over 220k sounds.  They've been installing for over 10 hours now and I just looked at the space on the disk drive, and it's nearly at 590gb.  The free space was at 880gb when I started.  How is it taking up an extra 200gb of space?   I personally believe they're being copied, installed and I will be able to delete certain copies, but is there anyone who can tell me if that's right firstly, second, why it is taking that extra space and third, will I be able to delete copies and shadows without interfering with the installation?  I'm not a computer programmer, I have tried Google but it's all jargon to me.