The league site is unthrottled. And krenzo is right, those audio files are just stereo by duplicating a single mono channel
Only way I'd play in game, mono refused to work for some reason. I'm still looking into that, in the mean time I'm writing a script for serious take on the NF voices. I used the exact same format and speed that the originals are running at. EDIT: Was able to get it working with mono, seems it was probably the format I first ported it to from.