query: bass string design

[Jim Coleman, Sr.]

Hi John:

One of the limitations is that imposed by the string winders. They are often
not willing to put such large wrap on so small a diamter core. For this,
you may have to go to Dave Sanderson's triple wrapped strings.

Jim Coleman, Sr.

On Mon, 2 Aug 1999, John Gunderson wrote:

> Dear List Mates
> It was pointed out to me that I had attached a "vcard" to my e-mail.
> Being a piano tuner, I am a modest guy by nature and would never
> knowingly engage in such shameless self-promotion (you'll just have to
> take my word on that). What I'm saying is that it was an accident, an
> oversight on my behalf.   I beg pardon of all,  it won't happen again...
> at least not knowingly.
> 
> Now my question.....  I am in the process of restringing a small baby
> grand.  I decided to try to rescale it.  I am using as my reference "The
> calculating Technician" by David Roberts.  After having spent some time
> on the the bass strings I have arrived at a scale that looks pretty good
> on paper.  My concerns have to do with the first 4 or 5 strings in the
> scale (A0 to E1 or there-abouts).  The original string for A0 measured a
> core diameter of .055" and an overall diameter of .230"  and a speaking
> length of 42".  This string, according to the calculations, had a
> tension ratio of only about 25% of its' breaking point and inharmonicity
> of the fourth partial of nearly 20 cents.   Both the hammer contact and
> the loudness/sustain factors were poor.  In my scale,  I have lowered
> the core diameter of this string to  .051" and raised the overall
> diameter to .275".  These changes bring the string to 40% of its'
> breaking point and lower the inharmonicity to 11.8 cents (they also
> improve the hammer contact and loudness/sustain factors).  But to do
> this I am significantly increasing the thickness of the wrapping.  My
> question is,  by doing so am I creating other string problems that I am
> not anticipating.  Is there an optimum ratio between core diameter to
> wrapping diameter.  Is there a point where the wrapping becomes too
> heavy for a given core?   Any suggestions/advice will be appreciated.
> Thanks...
> 
> John Gunderson, Associate Member,  North Jersey Chapter.
> 
>