SPL readings On My Unscientific DB SetUp for Denons

[hershon]

I earlier posted that when I used the SPL meter on my Denon receiver the DB levels using their 75 db test tones produced terrible sound- my DB's from the SPL reading (SPL aimed at the ceiling from my listening position, bass/treble at 0, all extraneous noise from my apartment turned off) were -7, -7, -8 for front speakers, -6 & -9 for rears & -9 for sub. Anyway, when I used the trial and error setting of 0 DB's for all speakers except the sub which is +2, the CD sound for me is fantastic. Shokhead suggested I read what my SPL levels are for these settings. When I then took the SPL settings for "0" on all speakers, +2 for sub I got the following: Front Left 81, Front Center 82, Front Right 83, Rear Right 81, Rear Left 83, Sub 84. What exactly do these numbers mean? Would you recommend tweaking these settings then- if so to what? Would you use the center setting as my foundation and therefore change the settings to +1 for Front Left, 0 Front Center, -1 Front Right, Rear Right +1, Rear Left -1 and Sub -2? Actually I just tried those settings out and they still didn't sound as good as 0 DB's for everything except +2 for sub.