A Baroque violin was initially made. It was then incrementally converted to a Romantic (modern) setup by replacing the short neck with a longer, more slender neck and adding a longer ebony fingerboard, a heavier bassbar and soundpost. This increased the total mass from 386 to 440 g. Several different Baroque and modern configurations, with baroque and modern style bows, were used for acoustical measurements and playing tests with professional violinists. Chladni patterns were similar in both versions and also when the bridge was placed below the soundholes. The Baroque version gave higher body mode frequencies than the Romantic. Placing the bridge below the soundholes lowered the frequency of the 800 Hz resonance to 600 Hz. Saunders Loudness Tests showed a response that varied strongly over the body resonances. For the transition from Baroque to Romantic setup, hand bowing showed an increase of 1 dB and machine bowing about 5 dB. The compliance of the body added to the air lowered the main air resonance by 5 Hz, equivalent to adding about 130 cc to the 2000 cc air volume. The top plate stiffness measured at the bridge feet was about 10 kN/m higher at the treble foot than at the bass foot, for all locations of the soundpost outside the treble foot. The stiffness at the bass foot remained constant. This was reversed when the soundpost was placed between the two feet: the stiffness at the treble foot was then lower than at the bass foot. The rocking and bounce frequencies of the bridge were lowered from 3000 and 6000 Hz respectively to about 2.5 and 3 kHz when fitted to the violin. Thinning the bridge waist lowered the rocking frequency. Recordings of performances on the violin were made for many combinations of physical state (baroque or romantic), type of string and bow, position of bridge, and others. Long-term average spectra for these recordings are compared here, and an online appendix includes these recordings in a way that allows them to be readily compared: www.phys.ul1sw.edu.au/music/people/mclennanappendix.html
Identifer | oai:union.ndltd.org:ADTP/258716 |
Date | January 2008 |
Creators | McLennan , John Ewan, Physics, Faculty of Science, UNSW |
Publisher | Awarded by:University of New South Wales. Physics |
Source Sets | Australiasian Digital Theses Program |
Language | English |
Detected Language | English |
Rights | Copyright McLennan John Ewan., http://unsworks.unsw.edu.au/copyright |
Page generated in 0.0015 seconds