iron wound strings

[John Delacour]

At 9:33 am +0200 26/4/07, Aras wrote:

>A "dumb" string does not produce partials - or very little. Sounds 
>like knocking your finger on wood.
>Such strings can be badly made or they can have too big mass for the 
>specific speaking lenght.
>You might have seen it in some small grands from Grotrian and others 
>where they have put in strings with 3 cupper wounds. They are not 
>able to vibrate even if heavy hard hammers are used.

The triple-covered strings fitted to Grotrian, Schiedmayer etc. baby 
grands work well enough if they are in good condition, given the 
limitation in size of such pianos.  Last week I made a set of strings 
for a Marshall and Rose baby grand which required 4 triple-covered 
strings and yesterday passed by the shop I'd made them for to hear 
the result, which was very satisfactory.  I think the fattest string 
I have every seen was from a Schiedmayer and measured almost 10mm. 
Nobody is going to rave about the low bass on a 4'3" piano no matter 
how the soundboard and strings are designed and how well they are 
matched, but high tension achieved by triple covers on a thick core 
is a necessity for certain makes of piano of this length.  There is 
no shortage of partials -- it's just that all the partials are 
inharmonic.  The strings will only be "dumb" if they are badly made 
or have deteriorated through damp, as you have said.

A "dumb" string, which will "rattle" or "buzz", is a string where the 
covers, for one reason or another, have lost their intimate and 
immovable contact with each other or with the core wire and where the 
energy, instead of being expressed in harmonic vibration is spent in 
shaking the copper and steel and creating heat.

JD