This thesis studied the influence of pitch, melodies and vocal registers on the formant frequencies of the English vowel /æ/ sung by a young female soprano singer. Previous studies by Sundberg and...Show moreThis thesis studied the influence of pitch, melodies and vocal registers on the formant frequencies of the English vowel /æ/ sung by a young female soprano singer. Previous studies by Sundberg and Skoog (1997), Sundberg (2008), Garnier (2010), and Deme (2014) have reported that classically trained sopranos utilise resonance strategies, also known as formant tuning, when F0 approaches or surpasses the frequencies of F1 (Sundberg and Skoog, 1997; Sundberg, 2008; Deme, 2014) and F2 (Garnier 2010). This is done in order to avoid a loss in acoustic energy. This present study observed that the soprano began F1 tuning once F0 went above 440 Hz. Although possible instances of F2 tuning were found, the soprano did not show a consistent pitch-related resonance strategy as she had for F1. It was found, however, that melodies and their placement in the vocal registers influence the manner in which the soprano tuned the frequencies of the first and second formants.Show less
Increasing effort into parallel single molecule force experiments has led to the development of acoustic force spectroscopy (AFS). Acoustic standing waves of MHz frequencies are able to exert...Show moreIncreasing effort into parallel single molecule force experiments has led to the development of acoustic force spectroscopy (AFS). Acoustic standing waves of MHz frequencies are able to exert forces on microspheres, which can be used for the manipulation of single bio-molecules. The performance of acoustic tweezers is greatly dependent on setup design and the proper driving frequency. The need for AFS flow cell design modeling software is apparent. In this thesis we present a physical model for calculating the acoustic frequency response of a flow cell. We have found that an oil immersion objective lowers AFS performance drastically as opposed to an air objective and that the optimal driving frequency lies around 10.3 MHz for our prototype flow cell. Limited by the 10 MHz cap of our AC driver and problems with flow cell assembly yields, we were not able to demonstrate an acoustic pulling force. We need to switch to an air objective and, in order to make AFS work in our laboratory, either a new AC generator needs to be implemented or a piezoelectric transducer with a thickness mode within 8-10 MHz needs to be included.Show less
