Speaker placement behind the screen

When your center speaker is behind the screen like yours is ... you need a special porous screen made to allow the dialog to come through it

THX encoded DVDs actually boost the dialog 3db for this purpose ... it's called an "X" curve if I remember correctly

This 3db boost to the center channel was recorded into the THX certified DVDs so you could place the center speaker behind the special purpose porous screen and the screen still pulled down the sound pressure level (SPL) by 3dbs to balance with the front right and left speakers

The opposite side of the coin is if you play a THX certified DVD disk and place the speaker in front of the screen ...the dialog is to loud and must be dialed  down in the processor which most HT enthusiastic do

Contact "Stewart Film Screens" and talk to someone in support .. they can explain it and help you out but you may have to replace the screen with the proper type for use with a speaker in back of it

• Horns are positioned facing the middle of the audience, not the back wall and ceiling.
  

• Measure your speakers at multiple locations and apply corrective EQ as needed.
  
• Control resonances to modern standards.
  
• Minimize or eliminate noise such as A/C units, outside sounds.
  
• Ensure all 3 speakers are operating optimally. Horns and woofers are both producing correct output.
  
• Ensure your overall speaker levels are properly calibrated.
  

• Some movies such as LoTR are produced with excessive dynamic range. To hear the softest voices requires too high a volume, which you then suffer through far too loud effects.