An automotive OEM requested Sound Answers to develop a pass-by-noise decomposition and synthesis tool. Test and analysis methods were developed to estimate the vehicle-level pass-by performance from component level data, both from physical and/or analytical sources. The result allows for the estimation of the overall vehicle-level pass-by noise along with the contributions to the total and dominant frequency content from each of the key noise sources. This information can be utilized in two distinctly different ways. First, the pass-by noise levels can be estimated for new component-level design alternatives, from either physical testing and/or analytical predictions. Secondly, a target pass-by noise level can be specified and the required acoustic performance for the dominant noise sources can be calculated. For further discussion on this topic please see SAE 2011-01-1608.