Sound-quality analysis of sewing machines

Abstract

Sound quality has become an important factor in consumer product development. Sound quality analysis procedure and results for six sewing machines ranging from entry level to professional grade machines will be presented. The focus of the study was to determine what consumers feel constitutes a pleasant sounding sewing machine and what structural modifications can be made to produce those sounds. The procedure consisted of forming small (15 person) then large (50 person) jury-based tests. These tests consisted of listening to various sound bytes and ranking the sounds as well as indicating why sounds are appealing or unappealing. The sound bytes were from actual sewing machines as well as computer generated sounds and modified machine sounds, which were constructed such that the spectral features most important in achieving a desirable product from an acoustic perspective could be statistically determined. The procedures and analysis of the jury testing results will be presented and discussed. This paper presents sound localization scans, indicating machine sound hot spots and possible sources for undesired sounds. In conclusion proposed modifications to machine structure to alter machine sound signature into a more sensory pleasant sound will also be presented.