The degree of twist is decisive, when all the rest is equal for a given gut (treatment, animal of origin, etc) for the breaking strength. I would hazard that .44 is made with the same twist by the same maker as .42. Which means if your instrument can take it, it will substitute for .42 just fine. .44 will be equally strong. The need to change the twist degree arrives at other diameter ranges, it appears. Interestingly enough, the working string length of historical instruments, drops slightly in relation to the mathematical formula, which means that, as Mimmo pointed out, the string twist was higher for the longer instruments.
alexander On Wed, 18 Feb 2009 12:29:08 +0100 Anthony Hind <anthony.h...@noos.fr> wrote: > Dear Mimmo and All, > If I have understood you correctly, there is a sort of > contradiction : as gut becomes thicker, it must be treated to make > it more flexible (higher twist and possibly softening chemicals), or > else it becomes inharmonic. The more flexible it is, for a given > diameter, however, the less tension it can stand (the Breaking Index > drops). Thus it is not the thickness itself, but the way thick gut is > treated that makes it break quicker than thin gut? > > You say the Index of a modern gut string is 260 Hz/m, but this is > only true true for the range of lute 1st string gauges. > "I mean 38 till 46 mm (more or less), where strings are made with a > very low twist and gut is made harder by chemicals." > > Does this mean that it is possible to substitute say a 44 treble > anywhere where it is safe to use a 42 treble, keeping exactly the > same breaking point in Hz; or does your "more or less" imply that > even for "38 till 46 mm" there will be a slight difference in twist > or hardening, which could mean the 44 would be less strong than the 42? > Of course I realize that such a substitution would increase the > playing tension, which may or may not be an advantage. > Regards > Anthony > > > with a 44 treble > Le 18 févr. 09 à 07:21, Mimmo Peruffo a écrit : > > > Hello guys, > > Just an observation: the suggested average of the Breacking > > Index of a > > modern gut string is 260 Hz/m. However, the full range of > > modern lute > > strings ranging between 240- 300 Hz.mt. > > This is true for the range of lute 1st string gauges. I mean 38 > > till > > 46 mm (more or less), were strings are made with a very low > > twist and > > gut is made harder by chemicals. The Breacking Index drop in the > > case > > that we are speacking of thicker 1st strings, were they are > > made with > > more twist than the lute chantarelles. > > Example: on the 1st bass gamba strings the Breacking Index drop > > of a > > semitone-tone than the lute 1st strings. > > In fact this is function of some technological things: the twist > > quantity and the use (or not) of some substances ables to do gut > > harder > > etc etc. > > If we go in the range of the violone 1st strings the breacking > > Index > > drop again and again because such strings are made very very > > high twist > > and without any chemical tretment able to do gut stiffer. This > > is why, > > in my wiew, the calculated Working Indexes (the product of the > > string > > scale X the supposed frequencies of the 1st strings) of the bowed > > instruments in the Praetorous tables drop step- by -step when the > > instrument became longer. So on Violins we are in the average > > of 210 > > HZ/mt while, on violones, we drop to arround 180 Hz/m only. > > Ciao > > Mimmo > > alexander ha scritto: > > To get on or off this list see list information at http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html
