Caillenne

So I'm trying to drop my pitch an octave similar to how Within the Ruins does it in a few of their songs (New Holy War towards the end for example). I'm tuned in Drop G# atm on a 7 string, whenever I drop it to -12 it just sounds really terrible. It sounds as if the strings were really loose and floppy. Anybody know if there's a way to get it much tighter and nicer sounding similar to how Within the Ruins has theirs?