Perception of timbral changes in a violin due to humidity exposure

Understanding the sensitivity with which experienced or casual listeners can discern the timbral qualities of violin family instruments is important for the construction and marketing of these instruments. An important tool for investigating such sensitivity is the listening discrimination test, which requires subjects to listen to multiple sounds and identify those that are the same or different. The present study uses listening discrimination tests to investigate the ability of people to reliably distinguish the effect of water absorption from humidity exposure on the sound of a violin. Audio files used in the test were synthesised by convolving the bridge force signal from a played violin with the measured bridge admittance of different violins that were placed in an environmental chamber for 24 h at each humidity level. Absorbed water in the wood of the violin body produces measurable shifts in the frequencies of signature modes. The goal of the study is to quantify the amount of shift that is perceptible in a controlled listening environment. Results of the study will be discussed, along with implications for discerning changes in violin response due to other causes.