Ooooo! Deaner the keaner gets the gold star again. wink

I am willing to bet that the THX standard is at 80 Hz because that is the point at which sound becomes non directional in the vast majority of rooms: say 95-99%. It wouldn't do to have a standard that didn't work for some people.

I have seen the same numbers as Dean. Bass can become non-directional as high as 200 Hz.

Fred

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Blujays1: Spending Fred's money one bottle at a time, no two... Oh crap!