It depends. Most of the time is taken up by extracting sound files. In the case of RWBY Voicepacks, I have to get video clips, cut them down further into the quotes I want, extract sound files from them, remove/limit the background noise in Audacity, amplify the sound in Audacity, and then I'm ready to go. If you already have the sound files, it only takes a couple of hours overall to make the SoundCues themselves (These are what play in-game when certain conditions are met). Of course, if you have a life outside of modding, it can take quite a bit longer.

im curious howlong does it usualy take you to make a voice pack ?