Film-Tech Forum ARCHIVE: Optimal speaker arrangement

This is topic Optimal speaker arrangement in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Randy Stankey (Member # 64) on 05-08-2009, 12:51 PM:

This is the arrangement of the speakers behind our movie screen.
(This picture has been posted before in another thread.)

Notice that the center horn is different than the other two.
My question is whether this is a sub-optimal set up or not.

It is my belief that all three speakers behind the screen should be identical (or nearly identical) so that the sound field is even as it goes out to the audience.

The person who I am consulting with on sound system upgrades seems to think that the center speaker cluster needs a longer horn so it will project dialog out to the back of the theater.

I think that is counterproductive.

Who is right?

Posted by Chris Slycord (Member # 4239) on 05-08-2009, 12:56 PM:

Would it be possible/feasible to test out both and see which works best in your room?

Posted by Louis Bornwasser (Member # 3063) on 05-08-2009, 01:48 PM:

Easy to test. Push left and center together and run dialog through one at a time.

If dialog is suitable, then I agree with you that all three should be the same. As a practical matter, however, there should be little in the center channel but dialog and left-over subwoofer information. You already knew this from listening to the monitor. Louis

Posted by Mike Blakesley (Member # 26) on 05-08-2009, 02:02 PM:

Wow, it must be nice to have that kind of space behind the screen. I'm jealous.

Posted by Steve Guttag (Member # 268) on 05-08-2009, 02:43 PM:

Your adviser is exactly wrong. If anything, the Center speaker should have a shorter horn (90-degree or greater)...depending on the room, the Left/Right speakers can be longer (60-degree or so). What you have is a 40x20 horn. I can just about guarantee that your don't have good coverage near the front of the theatre.

Steve

Posted by John Walsh (Member # 168) on 05-08-2009, 05:52 PM:

A bit off-topic, but is there something that can be done about the possiblity of echos behind the screen? Maybe you can 'fly' a whole baffle wall ... [Smile]

Posted by Randy Stankey (Member # 64) on 05-08-2009, 07:54 PM:

I have also been having discussions about a baffle wall. There's already a thread about that. There are probably some updates that I should post on that subject in the other thread.

Aren't the three speakers behind the screen typically identical?
That's what I've been pushing for.

The center speaker has seen some damage. Somebody was setting up the stage while I wasn't there. They pushed the center speaker a couple of feet too far down stage then they lowered the screen down on top of it. They busted the horn right off the top of the cabinet. I had to make a new top out of plywood.
It works okay now but, needless to say, the thing needs to be replaced.

When it is finally replaced, I want it to be the same as the other two.