Speaker placement behind the screen

We are a small independent movie theater with 100 seats. Our speakers are located behind the screen.  We often get complaints that the dialogue is too low.  Two questions: 1)  What is the optimal height for the speakers?   We've been told that they are too low (currently about 3 ft off the floor).  2)  Can we change the mix so that dialogue is louder without making music, sound effects, etc. louder?  Our head projectionist says no.

Any suggestions for references I can go to?  Thank you!

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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


Thanks for responding so quickly. Unfortunately, I don't know much about the specs of our sound system.  We do have a porous screen though, so the sound comes through the screen.  We run DCP mostly with an occasional blue ray.  I will contact the group you mentioned and talk to one of their techs.