Application brief and coverage target
Document the audience area, mounting position, room use, program material and acceptable control points. A speech room often begins around a 95–100 dB target at the listening area; live music may call for 110 dB or more. Those are planning anchors, not promises. The design must also account for local sound exposure rules, distance loss, reflective boundaries and the difference between short bursts and sustained output.
We turn the brief into a short equipment role list: input and mixing, processing, amplification, mains, subwoofers and monitoring. For systems with subwoofers, an 80–100 Hz crossover window is a common place to begin listening and measurement, but cabinet response and placement determine the final value.