Upper corner front left to lower corner rear right need to be 1/2 of 56.6 ft. That length works out to be the SQUARE ROOT of:
[(square root of: L squared + W squared) SQUARED + H squared]
Of course if your listening room has at least one wall which has (roughly) half its total surface area open to an adjoining room, you need to measure the longest top-to-bottom diagonal of the combined spaces ;-)) Have fun!
[(square root of: L squared + W squared) SQUARED + H squared]
Of course if your listening room has at least one wall which has (roughly) half its total surface area open to an adjoining room, you need to measure the longest top-to-bottom diagonal of the combined spaces ;-)) Have fun!