jdowning
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Larger Diameter Synthetic Strings? Anyone for Tennis?
During a recent search for larger diameter synthetic monofilament strings (i.e. greater than 1.05 mm diameter), I have checked out harp string
suppliers (available range 1.016 mm to 1.524 mm diameter in Nylon monofilament and up to 2.1 mm diameter PVF monofilament). I am interested in these
materials in order to carry out twisting experiments with the objective of extending the usual tonal range of monofilament synthetic strings beyond
the third course for plucked stringed instruments (as reported here):
http://www.mikeouds.com/messageboard/viewthread.php?tid=13379#pid91...
This search has led me to investigate sources other than suppliers of instrument strings. One potential source may (or may not!) be tennis racket
strings?
Tennis racket strings - once made exclusively from gut - are now available in a wide range of synthetic materials of monofilament as well as
multifilament (similar to silk strings) in construction. Racket strings should be elastic and durable - like instrument strings.
Tennis being a popular international sport these 'hi tech' strings are available at reasonable cost (about $4.00 to $15 for a 'set' or coil, of
sufficient length to string a tennis racket (about 12 meters) and in standard diameters of 1.10 mm, 1.20 mm, 1.25 mm, 1.28 mm, 1.32 mm, 1.38 mm and
1.43 mm.
The synthetic materials used for the strings are polyamide (nylon) with a specific gravity of around 1.15 and polyester with a specific gravity of 1.4
(greater than gut) - so the latter is particularly of interest.
This site gives a comprehensive coverage of what is available commercially :
http://www.stringforum.net/about_strings.php
Note - from the informative photo gallery on this site - not all strings are made of uniform cylindrical construction (some are hexagonal in section,
for example) so would not be considered as potential instrument strings.
Has anyone already tried synthetic tennis racket strings for oud basses (4th course and lower)? If so, what were the results?
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DoggerelPundit
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Just once. The neighbors complained about the racket. 
Seriously, good idea this. Up to your usual standard. It will be interesting to hear about any tests and their, er, net results.
-Stephen
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ameer
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You'll likely run into issues with the individual strings in a course colliding when plucked because the oud doesn't have the appropriate spacing.
Other than that I'm curious as well.
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jdowning
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Not sure if there would be a significant problem with strings colliding within a course as the vibration amplitude of modern metal wound plastic
strings is likely to be greater than plain, monofilament, high twist, polyester strings?
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ameer
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I can't be sure, but I think that amplitude difference will be more than offset by the large difference in diameter that would be required between the
third and fourth courses. I'm still curious to see what you come up with; if an oud is designed for it it could very well work.
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DoggerelPundit
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I am supposing some way would have to be found to increase the string surface purchase within the knot at the bridge. At least 3 turns is usual for
mono filament to avoid slip. Fatter strings might not allow that?
-Stephen
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jdowning
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Of course, at this stage it is not known how well twisted monofilament polyester strings will work but there is only one way to find out!
However, I expect that twisting the strings will increase string flexibility so increasing a string's ability to vibrate at a lower frequency level
than would otherwise be possible with an untwisted monofilament string. The higher density of polyester compared to nylon (and gut) should allow an
even further lowering of the tonal range.
Plain nylon is sometimes still used for the third course (rather than wound). However, if the loud 'brassy' sound of wound strings is preferred then
twisted monofilament polyester strings will likely be a disappointment even for a third course ( as it would also be for plain gut)?
Thicker plain strings would require a slightly different set up from wound strings.
Tying a firm knot at the bridge should not be a problem. Simply heat the end of the string with a flame so that it melts into a ball (to prevent the
end slipping through the knot) and then tie the string with the conventional knot used for thicker strings. The attached image shows the style of knot
- here used for an old gut third course string of 1.07 mm diameter.
I anticipate that the greatest potential for these strings will be for ouds tuned historically in the old way i.e. with the top string tuned as high
as it will go without breaking and the courses tuned a fourth apart. So, for example, a five course oud strung in gut (or equivalent twisted
polyester) with a 600 mm string length would once (centuries before Munir Bashir ) have been tuned A d g c' f'. At A440 reference pitch the calculated
diameter of the A course strings in this case would then be 1.24 mm at a tension of around 3.0 Kg force.
I imagine that this might well be feasible providing twisting the monofilament polyester string can provide the required additional degree of
flexibility for it to sound well. But we will have to see how it goes.
First task is to find an appropriate grade of tennis racket string (at minimum cost) from the bewildering range of manufacturers currently offering a
product. There are no suppliers or stockists in my locality so string stock suitable for experimentation and testing will have to be found on line.
[file]27113[/file]
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fayyazi
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i have used them on a Robab and it sounded fine, in fact it last longer than normal strings. the issue i think as mentioned above, is the different
gauges
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jdowning
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The available range of standard diameters for racket (or racquet) strings should be sufficient to cover the requirements for the oud (or lute) fourth
and fifth courses. String diameter can be adjusted - dependant upon the degree of twist applied and the temperature/time to set the twist as well as
the load applied during twisting and setting - not to mention the string material.
This article provides an over view of the methods of manufacture for tennis racket strings:
http://www.racquetsportsindustry.com/articles/2011/03/how_synthetic...
Given such a wide range of possibilities, the problem will be to find a suitable string for modification from a seemingly infinite choice.
As a starting point I have ordered a coil (12 metres - cost $6 or total $12 including shipping, handling and taxes) of a monofilament polyester 'soft'
co-polymer racket string 1.25 mm diameter (17 gauge) for initial trials - just to see what the possibilities might be.
A co-polymer is a mixture of polymer plastics the proportions adjusted by each manufacturer to achieve the physical properties required in a
string.
The variety of materials used for tennis racket strings is listed here:
http://en.wikipedia.org/wiki/Strings_%28tennis%29
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jdowning
Oud Junkie
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I have just received the tennis racket strings recently ordered for testing so will continue the evaluation and testing of these samples on the
'Twisted Nylons' thread.
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