Positioning line arrays isn't much different from other types of speakers. I would start by positioning them where other speakers have sounded best, then moving them incrementally and doing listening comparisons. One of the biggest detriments to good sound is placing speakers where a standing wave is generated. In my room, placing speakers too near the corners generates a 120hz peak at the listening position, which makes them sound very boomy. So I move them out and away from the corners until the peak is minimized. I measure this by placing a Radio Shack sound meter where my ears usually are and playing test tones from a Stereophile test CD.Danny Ritchie had mentioned his previous model line arrays, the Alpha LS, measured flat in an anechoic chamber, but it tended to overload his living room. He developed a network to control the bass. This isn't necessary with the Art arrays. Those 5.25" Dayton Classic woofers don't go as low as the speakers in the bigger line arrays, so excess output at the low bass frequencies hasn't been an issue.