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Recent trends show a growing demand for improved powertrain NVH and sound quality. In particular, there is little customer acceptance of tonal annoyances under any driving condition. Thus, powertrain NVH and product development engineers have a strong need to confidently determine acceptable noise levels for commodities that produce narrow band noise. Components such as power steering, transmission gears, pumps, engine timing chains, axle gearing, etc., all may produce significant tones under various vehicle conditions. The perception of the tone is highly influenced by its frequency and background noise. Background noise is composed of wind, road, and engine noise. A methodology and toolset of masking perception algorithms has been developed to meet these needs. The Masking Perception Analysis Software (MPAS) is used to address the development and verification of acceptable powertrain tonal levels as well as the diagnosis of tonal-related issues.

The Ford GT is the modern re-creation of the 60's era supercar. The powertrain sound quality of the vehicle must enhance its powerful nature, meet regulatory requirements, and maintain a targeted level of refinement. The Ford GT acoustic engineering team used time domain sound decomposition and sound synthesis techniques to determine the sub-system source sounds from surrogate vehicles. The donor source sounds (e.g. exhaust system) are recombined to produce the customer perceived vehicle listening experience from these sub-systems. Target sounds are developed by modifying sub-systems by level, frequency dominance, and order balance. Proposed target sounds are verified by a jury and the results are used for early target agreement and cascading to component targets. This exercise allows development of a customer focused powertrain target sound based on realistic hardware assumptions before any prototypes are available.