Thomas Zwieg, vice president and product development manager at Larsen Strings A/S in Denmark, calls for an internationally accepted standard for measuring string tension


Most string players view string tension as a choice between ‘soft’, ‘medium’ or ‘strong’. For violin makers it is important to select strings with the correct tension, to suit the tension and bridge pressure of each instrument.

For string producers, measuring string tension is a crucial part of string development, and quality control within that.

However, despite the fact that string tension is a parameter widely used by musicians and violin makers to compare and select strings, the values ‘soft’, ‘medium’ and ‘strong’ do not have a quantifiable fundament by which they can be compared; there is no internationally accepted standard for what they really mean.

Instead, string manufacturers have their own methods and test-parameters to measure string tension, and the tension levels stated – whether soft, medium or strong – depend on each company’s own definition.

Most string manufacturers publish tension charts to show the tension level of their strings, but given that these charts and the ways the tension levels are measured are not comparable between companies, the current system does not enable makers and players to choose strings suited to their instruments with sufficient ease.

As it stands, a string labelled ‘medium’ by one company may have approximately the same tension as a string classed as ‘strong’ by another.

When playing music, musicians tune to a universally defined pitch frequency – say A = 440Hz – to enable them to achieve a consensus. Why does no similar reference point exist for string manufacturers when defining string tension? If ‘soft’, ‘medium’ and ‘strong’ – and any variants in between – meant the same thing from one company to the next, in terms of tension and testing methods, it would be easier for string players and violin makers across the board to know what they were dealing with from one brand to another.

In the experience of Larsen Strings A/S, few violin makers or string players are even aware that such a problem exists. We would welcome an internationally accepted standard for string tension, specifying the methods and parameters of string tension measurements on violins, violas, cellos, double basses and all other stringed instruments. We believe that an international standard would be of great benefit to the whole string world, with a single string tension chart that is useful across the board – just as a tuning device shows the true pitch for A = 440Hz.

There is, however, a major barrier to this idea: currently only a very limited amount of information is exchanged between string manufacturers, and discussions on product development are rare. There is also little interaction between string manufacturers and violin makers. In an attempt to change this, all Larsen Strings A/S’s test parameters and tension data are available on our website. We hope this may lead to an open discussion of this issue in the string world. Perhaps a good first step would be for an independent research and development institution to make comparable string tension and testing data publicly available.

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