Speaker Positioning (part 2): One thing that will affect the sound from your line arrays is overall position when hanging: size and space in relation to the venue, the surrounding stage objects, and what if anything is blocking the sound. Experimenting with positioning offers near limitless possibilities for tweaking your sound, however, unless your paid by the hour (and have a day or more) this may be a bit consuming.
Hanging speakers in a real world space is not brain surgery, however it does require a bit of planning and some knowledge of basic geometry. Sound engineers typically need a basic floorplan, distances from the stage the sound will be traveling, and where various objects are likely to block the sound. Not all line arrays use the same sound producing technologies, however, it helps to think of invisible cones of sound emanating from the speakers themselves - the angle of every speaker in the line array will be pointing along an individual axis based on the overall angle the line array is hung. Anything coming in contact with that cone before and after it reaches the audience is going to affect the sound. Things likely to come in contact with that cone of sound include walls, floors, seats, and columns (or structural supports). Try to keep anything from blocking sound before it reaches the seating area. Obvious problems might include a part of the stage in front of a speaker, even if it is below the speaker it will affect the ability to move the air in front of it.
Speaker positioning basics:
* Experiment and then experiment some more with positioning - it will start becoming second nature - however with setup time being critical, use tools of the trade: certain line array manufacturers supply software making it easy to calculate speaker position to a given venue size; a tool to remotely monitor the angle of the line array during install certainly speeds this up - see the RAD2 line array; a laser distance finder of sorts.
* Sound path: Don’t let objects block the path of sound before it reaches the audience.
* Interior dampening/reflective material: Every space is different when it comes to acoustic properties, which will affect the sound quality. Learn as much as you can about the interplay between acoustically dampening and reflective materials and how it works. A venue with lots of reflective materials such as paneling and glass will lead to overly bright sound and can contribute to signal cancellations. Conversely it is possible to go overboard with acoustic dampening too, and muffle or drown certain sounds or voices.