5.1 surround setup in pro tools is different than the ITU, how should we place speake

[Rockman413]

Hi guys,
As we know, the 5.1 surround setup in pro tools is different than the ITU.
Which one is more for Film?
Should I place my speakers according to ITU(in a circle) or like the 5.1 surround pan in pro tools(in a rectangle)?


And for ITU, the front 3 speaker are quite close to each other, How about the Cinema speakers? Are close to each other like ITU, or they are actually like the one in PT--The left one is at the most left of the screen, right one at the most right of the screen.

[Craig F]

for a proper film setup

if you are sitting directly inline of the center channel the left and right are at 45 deg. from centerline left and right and all speakers are sitting in the same plain

in smaller spaces the left and right can toe in a little if there field of throw misses the mix position in the single plain

[ggegan]

I personally am not a fan of ITU speaker placement. It does not conform to any real world speaker configuration I have ever seen, either in movie theaters or home theaters. I don't know of any venue where all the speakers are equidistant from the listener. There is an additional issue with ITU where noise-like sounds such as rain, waves or traffic roar which are panned simultaneously to the front and surround speakers can exhibit an acoustic phasing effect with slight movements of ones head due to minute variations in the arrival time of the sound from the various speakers. I find it is nearly impossible to perfectly time align the speakers so that you avoid this issue with near field speaker systems that are equidistantly placed unless your head is locked in a vice in the perfect position. In near field mix rooms I generally put a 10 to 15 msec delay in my surrounds if they are close to equidistant to the front speakers in order to avoid acoustic phasing and more accurately replicate what I am used to hearing on a large dub stage.

[Rockman413]

Thanks guys!

So , I suppose we should place the speakers like the one in PT, right?

[Craig F]

I woudent call the panner's graphics totally correct but yes in that kind of a arrangement

[Branko]

I would just add that in most studios the listening angle between L and R is slightly over 40º, so don't place your L and R too wide.
Most of the audience in theatres listens to a much narrower stereo, 20-30º at best.