Can anyone advise please... Trying to set my system [KEF speakers, Marantz 6200, Rel 150 Sub]. I am using a Digital sound Pressure meter and have read previous posts on how to use it. I have amp at refrence 0db and set each speaker at 75db using C weighting and SLOW. My problem is which system to use to set speakers up as i am getting quite a difference between these three..THX optimer on T2 Disc , Video Essentials and amp test tones i am also a little confused as to how to set Sub up. The Video essentials and the THX optimer tools give similar results only in THX test all speakers need tweeking down approx -8db as it seems much louder. As i dont have THX speakers or amp i assume the response of these speakers ets is different therefore its probably unwise to use this tool..Right! I am also assuming setting up system from a DVD test disc will give better results as its the format used to listen to movies. But... Amp test tones seem more accurate in that i knew my front left speaker needed to be 2db higher than right as stereo image was out [vocals focused to right speaker rather than middle] Video Essential has front pair equal ! One other problem i have with Video Essentials is that the disc keeps refering to pro logic not DD 5.1 and does not seem to give a test signal to both rear channels is this a problem or am i missing something! Cheers for any help.