All the readings are taken from the sweetspot in the middle of your seating area or your favorite place to sit if its not in the middle but that will make the system sound really wierd for those in other places
. For your 1804(same as mine) the easiest way to calibrate(equalize) the speakers is go into the speaker set up screen and then set them all to small(this can be changed later if you desire) continue through the screens setting up the distances and finally you will get to the test tone screen, go into the manual test tone, so you can have it on longer if needed, and take a reading for the first speaker, they use - LF. Whatever that reading is(probably somewhere in the 70-75db range), use that as the base to set the rest as you move through the speakers adjusting each one up or down to achieve that first reading; Center will be next, then RF, Right surround, Center rear(if turned on), Left surround and finally the sub.
You don't have to set the speakers to 75db the main idea is to have them all sounding equal at the sweetspot, which achieves the nice even soundstage.
A trick for the vocals during the quiet scenes is to run the center 2-4db higher than the others and it doesn't cause any problems for any other effects.
