Center-fill speakers we use for large events (RCF HDL-10A)

A look at the center-fill speakers we use for larger events (RCF HDL-10A). Center-fill speakers are great for covering the area in front of a stage. However, not all events need a center-fill speaker. This video covers when to use a center-fill speaker (there is a little math involved).

Center-fill speakers are to cover only the area that the main FOH speakers are unable to; they are to supplement the main speaker system. Center-fill speakers should not be louder than the FOH speakers. Using too many center-fill speakers can cause phasing issues that will result in lower sound quality and potentially lower volume levels.

Center-fill speakers in this video: RCF HDL-10A.

Here's the basic math: (using a 20ft. distance with a 90deg. horizontal coverage horn)
2 * 20ft * tan(90/2)
40ft * tan( 45 )
40ft * 1 = 40ft (answer)