There is often some confusion surrounding string gauge and tension for bowed stringed instruments. For this article, I will concentrate on Violin strings, but the same principles apply to Viola, Cello and Bass.
The gauge of a string is the measurement of its diameter or in other words, its thickness. This was easily measured in the old Gut string era. The string was simply slotted a v-shaped tool which indicated the thickness – from which the weight was calculated and hence the downward pressure on the bridge.
With modern wound strings, this is not possible as thicknesses vary – thus the measurement is one of ‘tension’ from which again the downward pressure on the violin bridge can be calculated. The tension of the strings thus defines the pressure on the bridge – the higher the bridge and smaller the angle of the strings at the bridge, the greater will be the pressure on the bridge.
With modern strings, some manufacturers will list the actual tension, while others just offer a description such as, Hard, forte, stark or heavy – medium, mittel – or soft, thin, dolce, light etc.
In principle, the harder or stronger the string, it will result in a louder, fuller, and more powerful sound, but may also result in a slower response time. But also bear in mind that the violin must be robust, with a strong bridge and soundpost, otherwise you could damage your instrument. Generally, for older more delicate violins, the hard strings should be avoided.
Medium tension strings are the most popular today because they have been designed by the manufacturer to give an even, balanced tone and response. Once again the right string for you will be arrived at by some trail and experimentation, but I recommend that you try medium tension strings first when experimenting with new strings.
Thin or soft strings, require less tension to bring them up to pitch. They are used to soften up the tone of an instrument. These are less commonly used except in specific circumstances. Some professional players will mix their strings to achieve the right balance and sound for the instrument they are using, and it is not uncommon to fit a soft string to achieve this. I well remember a lovely old Cello which had a unusually thin table, to the extent that an overly tight soundpost actually dented upward. A set of soft Jargars was the only answer and resulted in a sweet, focused sound.
All this is important, but it is simply one of achieving the right balance between you, your instrument and the sound you wish to achieve.
Next week we will discuss actual strings.