Today's Lesson

What do you do if you find yourself in a large venue or an outdoor venue, and your main PA loudspeakers just don’t seem to cover the full audience area adequately?

The best solution here is to make use of fill or delayed loudspeakers. But how do you know where to best place them?

The ’Inverse Square Law’ states that in a controlled indoor environment, direct sound will decrease in strength by 50 % (-6 dB) every time it doubles in distance from the source. We can use this information as a guide to help find the best location for delayed and fill loudspeakers. 

Take the closest point covered by each loudspeaker and the farthest point covered. If the goal is to keep consistent audience coverage with no more than a 6 dB difference between the loudest and quietest point in the audience, you will need to place and orientate your loudspeakers accordingly.

The rule to follow is that, twice the distance ‘a’, should always be greater or equal to ‘b’ (2a > b). Following this principle, we can more accurately place our loudspeakers throughout the venue to get the best coverage throughout the listening area. 

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