Scaling questions

[Tom Rush]

Jim Bryant wrote:
> 1. Have you Called Mapes or Schaff?  It is possible that they 'might' have
> the scale for at least the bass strings.

Haven't yet.  I'm assuming (perhaps wrongly) that the bass scaling was
not modified.

> 2. Is the Knabe a 85 note or 88 note instrument?

88.

> possibly there were originally wound strings past the break.

Thought of that.  The arrangement of the hitch pins seems to rule out
this possibility.

Vince Mrykalo wrote:
> Have you looked in John Travis' book "A Guide To Restringing" for
> your Knabe scale?

Yes, but I didn't really find anything similar.  BTW, thanks for the
tip about Dave Roberts' book, I'm going to see about ordering a copy.

Mark Dierauf wrote:
> If the bridge or agraffe line curves back toward the strike-point, then the
> tensions will fall and the inharmonicities will rise - and using wound strings
> is the only way to manipulate both these properties independently to best
> blend in with the strings above and below this section.

The foreshortening is not really that bad...it *is* a 7-1/2 foot piano,
after all.

> >> since using a set tension of 160-180 lbs. gives undesirable results.
>
>   I'm not sure what you mean by 'undesirable results', but if you mean tonal
> quality, tunability, and pitch stability, then you need to be looking at more
                                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^
> than just the tension.
  ^^^^^^^^^^^^^^^^^^^^^
Exactly.  I want to know what to look at, i.e. how to calculate the best
wire size here.

You are obviously a proponent of rescaling this area with wound strings.
And you make a good point.  However, I am more interested in coming up
with a reasonably good approximation of what was there originally (and
I firmly believe they were not wound strings).

There are prime examples of pianos in this size range that use 68 plain
wire unisons (Steinway B & D, to name two), and I can't believe they do
it that way just because they don't know any better.  :-)

To all--this is helpful and interesting, and I thank you for your input.

--
Tom Rush
tarush@chatt.mindspring.com