The room size/characteristics do come into play. Loud for me is -12db for CDs, and -9db for movies. Comfortable is about -15db. I've never had the system at +5db. I think 0 was as high as I took it, and it was make your ears bleed loud.

LFR1100 Actives,QS10HPx2,QS8x2,EP800,M3x4,M3x2 (Wood),M5HPx2 (Wood),AxiomAir,ADA1500-8,ADA1500-7