Adding Support to PT_PT

Hi, I'm training a text aligner to improve tts quality in European Portuguese, and while I was browsing the code, I found an instruction, which I'd like to know what is it needed for.  
It's this file Utils/ASR/models.py and it's line number 19: "self.n_down = 1" what's the purpose of self.n_down, could it be different from 1, in which context? 
Thanks a lot
