I first calibrated all speakers to 85db. When my receiver is turned up to "00" all speakers hit 85db on my rat-shack meter. That part was easy. Then I thought I would double check with the receivers test tones (Denon 1804). The receiver turns itself up to "00" and plays it's test tones...they were all even. It only hit 80db on my meter but they were all even. I smiled happily and moved to the sub. When I played that chapter on the disk I thought I should do it like the other chapters but when I set my volume to "00" it's not 85db it's more like 90db. How can I calibrate when the levels on the test tones are different? I have my sub set at the same levels as the rest of my speakers using the internal test tones of the receiver...everything hits 80db which as I stated above when I play the chapter "6 channel speaker balance" they all read 85db. (80db on the receiver=85db on the disk) wouldn't it stand to reason to also just set the sub up the same way...80db on the receivers test tones=85db???