Materials Engineering of Violin Soundboards by Stradivari and Guarneri

Cheng-Kuan Su; Szu-Yu Chen; Jen-Hsuan Chung; Guo-Chian Li; Brigitte Brandmair; Thomas Huthwelker; John L Fulton; Camelia N Borca; Shing-Jong Huang; Joseph Nagyvary; Hsiao-Han Tseng; Chih-Hui Chang; Dai-Ting Chung; Rafael Vescovi; Yi-Shiuan Tsai; Wenjie Cai; Bing-Jyun Lu; Jia-Wei Xu; Chia-Shuo Hsu; Jun-Jie Wu; Hao-Zhi Li; Yu-Kai Jheng; Sheng-Fong Lo; Hao Ming Chen; Yi-Ting Hsieh; Po-Wen Chung; Chien-Sheng Chen; Yuh-Chang Sun; Jerry Chun Chung Chan; Hwan-Ching Tai

doi:10.1002/anie.202105252

Materials Engineering of Violin Soundboards by Stradivari and Guarneri

Angew Chem Int Ed Engl. 2021 Aug 23;60(35):19144-19154. doi: 10.1002/anie.202105252. Epub 2021 Jun 27.

Authors

Cheng-Kuan Su¹, Szu-Yu Chen², Jen-Hsuan Chung³, Guo-Chian Li³, Brigitte Brandmair⁴, Thomas Huthwelker⁵, John L Fulton⁶, Camelia N Borca⁵, Shing-Jong Huang⁷, Joseph Nagyvary⁸, Hsiao-Han Tseng³, Chih-Hui Chang³, Dai-Ting Chung⁹, Rafael Vescovi¹⁰, Yi-Shiuan Tsai¹¹, Wenjie Cai¹², Bing-Jyun Lu¹³, Jia-Wei Xu², Chia-Shuo Hsu³, Jun-Jie Wu¹⁴, Hao-Zhi Li¹⁴, Yu-Kai Jheng¹⁵, Sheng-Fong Lo¹⁵, Hao Ming Chen³, Yi-Ting Hsieh¹³, Po-Wen Chung¹¹, Chien-Sheng Chen¹⁴, Yuh-Chang Sun¹⁶, Jerry Chun Chung Chan³, Hwan-Ching Tai³

Affiliations

¹ Department of Chemistry, National Chung Hsing University, Taichung, Taiwan.
² Department of Optics and Photonics, National Central University, Taoyuan, Taiwan.
³ Department of Chemistry, National Taiwan University, 1 Roosevelt Road Section 4, Taipei, 106, Taiwan.
⁴ Hilgertshausen-Tandern, Germany.
⁵ Swiss Light Source, Paul Scherrer Institut, Villigen, Switzerland.
⁶ Physical Sciences Division, Pacific Northwest National Laboratory, Richland, USA.
⁷ Instrumentation Center, National Taiwan University, Taipei, Taiwan.
⁸ Department of Biochemistry and Biophysics, Texas A&M University, College Station, USA.
⁹ Chimei Museum, Tainan, Taiwan.
¹⁰ Argonne National Laboratory, Lemont, IL, USA.
¹¹ Institute of Chemistry, Academia Sinica, Taipei, Taiwan.
¹² School of Cultural Industry and Tourism, Xiamen University of Technology, Xiamen, Fujian, China.
¹³ Department of Chemistry, Soochow University, Taipei, Taiwan.
¹⁴ Department of Chemistry, Fu-Jen Catholic University, New Taipei City, Taiwan.
¹⁵ Department of Forestry and Natural Resources, National Ilan University, I-Lan, Taiwan.
¹⁶ Department of Biomedical Engineering and Environmental Sciences, National Tsing-Hua University, Hsinchu, Taiwan.

Abstract

We investigated the material properties of Cremonese soundboards using a wide range of spectroscopic, microscopic, and chemical techniques. We found similar types of spruce in Cremonese soundboards as in modern instruments, but Cremonese spruces exhibit unnatural elemental compositions and oxidation patterns that suggest artificial manipulation. Combining analytical data and historical information, we may deduce the minerals being added and their potential functions-borax and metal sulfates for fungal suppression, table salt for moisture control, alum for molecular crosslinking, and potash or quicklime for alkaline treatment. The overall purpose may have been wood preservation or acoustic tuning. Hemicellulose fragmentation and altered cellulose nanostructures are observed in heavily treated Stradivari specimens, which show diminished second-harmonic generation signals. Guarneri's practice of crosslinking wood fibers via aluminum coordination may also affect mechanical and acoustic properties. Our data suggest that old masters undertook materials engineering experiments to produce soundboards with unique properties.

Keywords: ICP-MS; IR spectroscopy; NMR spectroscopy; X-ray absorption spectroscopy; cultural heritage.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.