Audio system design for cruise ships

Abstract

The design of audio systems for cruise ships introduce several acoustic challenges. The two leading challenges to overcome are ambient noise level and specular reflections. Ambient noise levels can reach 55 dBA and in many cases, higher. A majority of these noises are caused by engine vibrations, and HVAC which tends to be the leading cause of high noise floor levels. Audio systems are designed to compensate for such high ambient noise levels by distributing sound levels selectively throughout the facility. Another challenge to audio system design is specular reflections. This reflection is a delayed audible signal bounced off a surface at equal to or slightly less than the level of the direct sound with time as the variable. The problems caused by these reflections can vary from tonal coloration to echoes. Many surface materials not found in traditional showrooms can have very low absorption coefficients around the 1000 Hz–4000 Hz margin. Such surface materials include heavy plated glass windows, smooth tile flooring, etc. Interaction with the Interior Architect is crucial when designing the audio system. Many of these common problems can be minimized by room modeling through computer simulators for acoustics in the design phase.