I have the volume on my sub about half way about 9-10 o'clock. Should I turn it all the way down and use the SUBW level on my receiver? Does it matter as long as I have the db's matching my mains? With the spl meter of course. I'm also using the Denons crossover via the LFE set at 80, what do I set the subs crossover at? Turn it all the way up, so the sub uses the denons internal crossover.