I have the 1723 Towers and I also use 80Hz and balance my subs for MaxSPL. I’v noticed if you set the Towers to 60Hz down to 40Hz you losing 3- 6dB of bass output on the subwoofers when I ran a test. Would like to get my hands on duel 1723 2S’s to replace my Starke Sound SW12’s that will give me MaxSPL to the sub low end that I need.