The sound quality of the noise from a product is of ever-increasing importance when assessing the total quality of the product. For products ranging from cars to hand tools, not only the level but also the quality of the noise it makes is part of what attracts or repels the customer; the right sound can lead to increased sales.
Many factors come into play in the sound quality evaluation process. Traditional objective measuring and analysis methods, such as A-weighted sound pressure and FFT analysis, are not enough to analyse product sound. Customer expectations and jury testing are also important factors for determining acceptable sound quality because, in the end, only the human ear can tell the designer whether or not the product has the right sound.