rojaros
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An A string for the bass
Hello,
I'm trying to figure out, which string would suite as a single deep A medium tension bass string for my new Sebastian Stenzel 7-course oud.
I tuned a Daniel Mari C- String down, and it works somehow, but is to flabby.
Any suggestion appreciated; best wishes
Robert
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fernandraynaud
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If you provide scale length, an ideal gauge can be calculated. But basically any Spanish guitar low E string (silvered copper on nylon filament) can
work. Mari's C string is usually a 0.040". That's even a bit flabby as a C. A 0.045" might work as an A.
If you have a specific Spanish Guitar E string in mind, and have its tension on a guitar at scale 650 mm, enter its (metric) diameter, E note and 650
mm scale into Arto's String Calculator, then adjust the density until the tension agrees with what the manufacturer provides, it will be something
over 7000 kg/cubic meter. Then change the scale to your oud's, say 615 mm, and drop the note to A, and you will get the tension on your oud tuned to
A. Make sense? That should not exceed 5 kg, preferably under 4.5kg.
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rojaros
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Hi Thanks for your contribution, fernandreynaud.
According to your procedure even with d'Addario extra hard tension concert guitar E-String I'd end up with something around 2,7 (composit 2,9 kg)
tension, which is nowhere close to 4,5 kg.
Did you have any specific concert guitar string in mind?
BTW as typical densities I get through String calculator something below 5900 kg/m^3. Did I make a mistake?
best wishes
Robert
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fernandraynaud
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No, you are correct if we accept that 14.5 lb tension. The density of a D'Addario low E hard tension 0.044" works out to 5750 Kg/m^3. On a guitar with
650 mm scale tuned to E we obtain 6.59 kg tension, which is what JustStrings says D'Addario provides. So that's our reference. But as you will see
below, we are right to double-check each other's calculations.
On a 615mm scale oud tuned to C the tension of the 0.044" works out to 3.7 Kg, which is fine, nicer than the rather flappy Daniel Mari 0.040". If you
drop it down to be tuned to A, the tension works out to 2.63 Kg. That's very playable, but you could easily take a thicker string. D'Addario makes a
0.045" and a 0.048", even up to 0.060".
D'Addario (by the way) provides oud tensions, only up to a 0.043", but the data they provide lend credibility to our little calculation, as they state
3.86 kg for a 0.043" tuned to C on 610 mm scale. It's one of the most useful tables available, since almost all oud strings are made the same way, of
the same materials. Here's this mother of oud tensions table:
http://www.khalafoud.com/Images/Misc/Daddariosingletensions.pdf
Some wound strings made in the Middle East use a thinner winding wire (of plain unsilvered copper), and more of the cheap nylon fluff, resulting in
lower density, hence lower tensions. These are often found as "factory strings" on ouds, but are generally of poor quality, with the windings easily
broken, and are best replaced immediately.
D'Addario also provides some seemingly different tension data in a table at:
http://www.daddariostrings.com/Resources/JDCDAD/images/tension_char...
It looks like the thicker gauges are in there, page 9. The only problem is they rate a 0.043" tuned to E as 15.2 lb and not 14.0 lb. They use a guitar
scale of 647.7 mm, which agrees with our 650. So it seems there's a slight error somewhere. If we use the 15.2 lb reference point, a 0.043" works out
to 6360 Kg/m^3. Hmmm, a little more. That gives us 3.91 Kg tuned to C on the 615 mm oud, and 2.78 Kg tuned to A. So at least it's not a big
difference. The truth of the matter is that a string rated at 0.043" has been measured anywhere from 0.0415" to 0.0445", so maybe we just have to
accept life as it is. You should be able to use the data they provide (up to a 0.054") to find your dream A string 
There's another reference point in a classical Extra Hard 0.045" that JustStrings lists at 15.7 lb -- and again Page 9 shows a slightly higher 16.7
lb.
Maybe there's something I'm missing, if you find it, let us know. Maybe you have the patience to figure it out. D'Addario is not a newcomer to stupid
misprints. If you REALLY want to get your mind blown, look up the D'Addario J95 oud set, for instance on JustStrings.com.
http://www.juststrings.com/dad-j95.html
The set is labeled all wrong, using the Turkish notation (which is transposed up a 5th) as if those were the real notes, and THEN some cretin
calculated tensions based on those notes!!! In all fairness, as if things weren't hard enough, the Ottoman court had to court disaster when they
adapted European notation. As SaedMuhssin says:
... when a Turkish musician sees a note in the second space (corresponding to western or Arabic "A4") she will call it
Re, and play an E (not D because of the tuning).
So when D'Addario makes an oud set, she will call it crazy. They state that the third course is at a mere 21.6 lb, almost 10 Kg tension. I'd sure like
to play THAT oud for the few minutes before it crashed. See why I said it's good to check ? 
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rojaros
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Hi Fernandraynaud,
I appreciate very much your effort to help me ... OK, so our calculations are same; my oud has 600mm scale, so I end up a little bit lower, but it
seems to be a fair tension, if I get 2,7 kg or so.
I just ordered some d'Addario E-strings and also Prymid 1441 and 1443 lute strings, as was kindly suggested to me by LeeVaris in a U2U message.
I'll let you and everybody know my findings ...
best wishes
Robert
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