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CHAPTER 1 Fundamentals of Audio and Acoustics End of array A 10 log A 2A = -3 dB 2A Pressure maximum due to phase summation 2D x Pressure minimum due to phase summation D x End of array FIGURE 1.25 The finite line array has gained wide acceptance among system designers, allowing wide audience coverage with minimal energy radiation to room surfaces. Courtesy Syn-Aud-Con. of the points will be the most in phase on a plane perpendicular from the array and equidistant from the end points of the array. As the point of observation moves away from the midpoint, phase interac- tion will produce lobes in the radiated energy pattern. The lobes can be suppressed by clever design, allowing the wave front to be confined to a very narrow vertical angle, yet with wide horizontal cover- age. Such a radiation pattern is ideal for some applications, such as a broad, flat audience plane that must be covered from ear height. Digital signal processing has produced well-behaved line arrays that