I recently purchased an HTR-5730 bundle with speakers. I like the unit but I am confused. I have 5 speakers and a sub connected. The volume "range" goes from -80 db (80 %) to +16 db (16). so it appears that I am only getting 16% of the potential output to my non-audiophile mind. Is this correct or is there a problem hear? (pun) I would expect to get significantly higher volume than I am..