No. It's not possible. You cannot change mixed audio (WAV/PCM/LPCM) into midi. (There are some programs that say they can do it (kind of -- it's a hack), but you need to judge the results yourself.)
However, what you can do is connect your computer to some external speakers, or another sound system, and play GDT through that system. You need to run GDT to actually play it though.
Some DJs and performers have used GDT in similar scenarios. I don't know the details, but I've had a few tell me. I know GDT is used in recording studios for exactly this kind of thing -- play the altered audio for a performer to record against.
I hope that helps out.