Nak Tarhu Strings
Cello Strings: a 5-string cello set is used, tuned an octave above normal cello pitch. Cello strings are the choice of most Cretan lyra players, as well as for some contemporary Indian sarangi players. Having been developed over centuries for the extremely rigorous demands of the cello repertoire, these strings respond well across a huge variety of techniques and musical requirements.
Horse-hair strings: strings made from horsehair have been used by various cultures over the centuries, with the use of natural hair often being replaced by nylon in recent years. The individual strands of such strings are all completely straight and parallel to each other, as seen in the horse-hair used in a musical bow – there is no twisting or wrapping involved. Instruments using this type of string include the Morin Khuur from Mongolia, the Jouhikko from Finland and the Rebab from Egypt.
Soon after the lyra tarhu was made for Ross Daly he re-strung it, changing from cello strings to horse-hair style strings that he made out of nylon. When the nak tarhu was created, it likewise used horse-hair style strings. Unfortunately using horse-hair style throughout on a 5-string instrument meant that the bass string became very thick (nearly 4mm in diameter) and was consequently limited in the range of sounds and techniques it was capable of supporting.
Metal UDMS strings: Horse-hair and nylon are at one end of the spectrum of the materials that can be used for this type of string - but when it comes to using fine tungsten wire for the fibres instead of horse hair or nylon, the term “horse-hair style” becomes a bit questionable. They can also be called Uni-Directional Multi-Strand strings (UDMS), defining them by their structure rather than by the material used.
Very fine metal wire in a UDMS string behaves in a similar way to horse hair – the individual strands combine together so far as string weight is concerned, but they remain separate so far as string stiffness is concerned. If very fine tungsten is used, the stiffness remains low, but tungsten’s extreme weight makes the string heavy with very little overall diameter - a tungsten UDMS bass string is approximately 1/20th the diameter of a nylon UDMS bass string tuned at the same tension to the same pitch. This radical change in string diameter has a proportionately radical effect on the sounds the bass strings can make.
At the current stage of experiments with this type of string (July 2019), indications are that the best results for a 5 string nak tarhu set would come from: strings 5 and 4 – tungsten 0.08mm; strings 3 and 2 – brass 0.1mm; string 1 – steel 0.1mm. String #2 may also be better in steel rather than brass. The graduation in metal types goes from heaviest (tungsten) to lightest (steel). This helps in not having bass strings too thick or treble strings too thin (steel is less than half the weight of tungsten and is therefore thicker for the same pitch).
Tungsten is available in such small diameters that working with the wire can be extremely difficult – at the thinnest end of the range, tungsten wire is so fine that it can only be seen by the naked eye in very particular lights. 0.08mm was therefore chosen as the finest that is practicable for string-making purposes. Brass and steel are not readily available thinner than 0.1mm, so that was the diameter chosen for those metals.
Metal UDMS strings present the player with a wider tone-colour palette and greater sensitivity than either of the two other string types. The sound is more multi-dimensional than with cello strings and more even than with nylon UDMS. Hopefully as the use of these new strings develops and is further refined, the nak tarhu will be able to realise more of the potential contained within its design. If anyone is interested to work with these strings, the wires mentioned above are available from:
NB Tungsten wire is rather expensive - as of 2019, $190 for 500 mtrs. While 500 mtrs can make quite a few strings, it still works out to be over $4000 per kg………compared to brass wire which currently costs $15 per kilo (the brass wire mentioned above is used in Electrical Discharge Machines and has to be cheap to be viable for this application). While tungsten has very particular qualities, it might be worth considering buying a spool of brass wire first, see if you like the idea and only buy tungsten if you really need its characteristics.