double-wound strings

[John Delacour]

At 5:19 PM -0500 12/8/01, Clyde Hollinger wrote:

>I posted this question a couple days ago and got no helpful answers.
>While tuning a 1956 Baldwin F grand piano I noticed it had no
>double-wound strings.  Single-wound strings the whole way to the
>bottom.  How common is this?  I haven't noticed it before.

It's very common, and the further you go back in time the more common 
it is.  All Steinways until the S was introduced had single-covered 
strings all the way down and all Bechsteins before the A (6'0"). 
These two makers seem to have made it a point of religion.  Many 19th 
century German makers did the same, but the double-covered string was 
common even before 1850 in England (eg. Broadwood) on both uprights 
and grands.  There was generally a practice of taking the bichords 
further down in the scale.  Yamaha and Kawai only 20 years ago were 
faithfully following the Steinway religion and the first Kawai GS-30s 
I sold came in with all single-covered.  These went straight in the 
bin and I put on my scale.  Quite soon after that, they began to 
scale the piano better.

No absolute rule can be made, and a good example is the Steinway 
Miniature.  This piano has a bottom string only 137 cm. long with a 
25 core and a 210 cover.  You'd think you could do better than that 
and use a thinner core with a double cover to get more tension in the 
string, a purer harmonic content and more power.  In fact, it makes 
very little difference.

However, very roughly speaking, and all other things being equal 
(which they aint), it would be normal now to use all single-covered 
only on pianos of about 7' and longer and all double-covered on a 5' 
piano and an increasing number of single-covered singles between 5' 
and 7'.  Strings require a certain minimum strain to sound the way we 
like them nowadays and to get this strain, we need to put more copper 
on some than is possible with even the thickest cover.

A thickish single-covered string is considerably stiffer than a 
double-covered string of the same diameter, especially than a d/c 
with a close cover ratio.  This means that the fundamental is 
favoured and the attack is better.  You can play bass staccato runs 
on a Steinway but on something like a Bösendorfer, the damper has 
come down before the string has begun to work properly.  There are 
people, including piano-makers, who will strike a bass note and hold 
it down and take all day to listen to that wonderful rich sound as 
the harmonics sing out and the note sustains for half a minute, and 
say that's the way it should be.  There are others who consider that 
the piano must be manageable and flexible and responsive when playing 
a wide range of music and not just funeral marches and church slush.

I think most people today (because it is partly a question of the 
Zeitgeist) would want as many single-covered strings as is consistent 
with good strain and then (in pianos less than 7') a few 
double-covered strings at the bottom to keep up the tension and the 
tone-quality.  However, there have obviously been several schools of 
thought for a long time.  A comparison of a 6'6" Blüthner, a 
Steinway, a Schiedmayer. a Brinsmead, all of say 1900 will show four 
completely different approaches to the question.  Nowadays Steinway 
are out there on their own and even they have yielded to 
double-covered strings on the Model K, after a century or so.

That's just a rough description of the case.  Feel free to ask any 
detailed questions.

JD