Infrared and NMR spectroscopy have possibly revealed one of the great secrets of the violin makers Stradivari and Guarneri del Gesu - they used chemical wood preservatives to help preserve their instruments and to improve the tonal quality. The discovery could help modern-day violin makers emulate more closely the properties of irreplaceable violins from the 18th Century and well as providing music conservationists with new insights on how to best preserve the antique instruments.

Joseph Nagyvary at Texas A&M University, in College Station, and colleagues, reveal in a brief communication to the journal Nature how the maple wood used by the celebrated craftsmen could have been chemically processed before the violin makers even began crafting the wood. The researchers have analysed in detail the organic matter from small samples of shavings retrieved from the interiors of five antique instruments during repairs.
The team compared their results with samples from modern violins from eastern and central Europe, as well as data obtained from violins made in Paris and London at similar times to those of the Cremonese masters. The researchers offer an explanation for the differences which reveal several differences in their carbon-13 solid state NMR spectra and attenuated total reflection FTIR spectra. They suggest that the Cremonese masters used wood that had been treated - oxidation or hydrolysis - by regional woodsmen to aid preservation and that the mechanical and acoustical properties were also improved by this treatment.

"Our violin case studies may inspire a more chemistry-based approach to violin-making," the researchers explain. Indeed, Nagyvary is a violin maker himself and is already exploiting these and other research results to mimic the tonal qualities of Stradivarius and Guarnerius violins. Computerised signal analysis provides a fingerprint of the sound of the old violins and the new models are then reworked until their tone matches precisely the originals. The latest spectroscopic analysis of original Cremonese violins may allow the company to pre-treat the wood it uses to more closely match the originals.
Nagyvary procured the samples, perhaps the most difficult task, and instigated the research. However, he told us, "all the real work was done by colleagues elsewhere". He collaborated with the NMR lab at Colorado State University because the researchers there, including J. DiVerdi, are pioneers in wood solid state NMR. Noel Owen of Brigham Young University is an expert in the field of wood FTIR. "Their expertise was essential," Nagyvary told spectroscopyNOW.

Related links:

• Nature, 2006, 444, 565
• Nagyvary Violins

Article by David Bradley

The views represented in this article are solely those of the author and do not necessarily represent those of John Wiley and Sons, Ltd.