That isn't how it works, my friend. 130db at 30hz from your subs and 130db at 1000hz from your midrange horns won't sum to be a greater output than 130. If your theory was correct, then when you meter this, it should meter over 130 db. It won't. A SPL meter does not register an aggregate SPL level, rather, they are either frequency specific or weighted such as dBA. dBA is a more accurate measure of SPL for daily use because it weights different frequencies that are perceived to be louder to the human ear. A straight dB meter which is what the TL is does not do that because you're only interested in the bass frequencies and as such, all you'll be metering is 130db.