Wrapped Bi-Chords in Tenor

[Delwin D Fandrich]

harvey wrote:

> Off-subject, but I wish the latest incarnation of the 'A' had not used the
> A4 scale. Some of the vintage A's were really sweet, but I don't like the
> results of running that many wrapped bichords so far past the break. Del,
> if you see this, feel free to jump in!
>
> -jh-

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Jim,

I'm not that familiar with all of the specific M & H scales, but...

I'm not at all opposed to using wrapped bi-chords up into the "tenor" section of
a short scale.  There is no law that states that the bass/tenor break must occur
at the same spot as the transition between plain steel tri-chords and bi-chord
wrapped strings.  In fact, I'm coming to believe that in shorter scales -- i.e.,
those below about 210 to 215 cm (6' 10" to 7' 1") -- a better acoustic
transition can be made if both of these transitions do not occur at the same
point.

However, -- and this is a really big "however" -- if there are bi-chord wrapped
strings used on the tenor side of the bass/tenor plate break, they really should
terminate on a separate bridge.  To blend well acoustically they do need to be
somewhat shorter than their plain tri-chord neighbors.  This cannot be done
unless they are placed on a separate bridge.  This separate bridge can be
treated either as an extension of the main tenor bridge -- i.e., attached to the
body of the main bridge -- or as a completely separate bridge.  I've
experimented with both and, at this point, I don't really have an overwhelming
preference.  I'm leaning toward connecting them, but we'll see.

In most older piano designs, plain steel strings are used far too low in the
scale for good acoustic balance.  Even the above mentioned 210 to 215 cm scales
could probably best use as many as 25 to 27 wrapped string unisons.  Shorter
scales -- pianos less than approximately 180 to 185 cm (5'11" to 6' 1") should
be using up to 30 or 32 unisons of wrapped strings.

One other point.  If bi-chord wrapped strings are used on the tenor side of the
break, they should form a continuous scale progression with those on the bass
side of the break.  In other word, there should be one continuous scale designed
for all of the wrapped strings and it must flow smoothly from A-1 through to the
end of the wrapped bi-chords -- however many there may be.  This was rarely --
if ever -- done in early string scale designs.  Which means, of course, that it
is rarely -- if ever -- done today.  The most common practice with older string
scale designs was to simply terminate the bi-chords on the same bridge body as
the plain steel tri-chords.  This makes the acoustic transition between the
wrapped and plain strings a bit awkward.  It is a little bit more expensive to
do this properly because of the need to make, align and mount three separate
bridges -- or to make a tenor bridge with a short extension for the bi-chords.
And what do you expect for only $40,000 or $50,000, anyway?  Good scaling?

If you've noticed a lack of discussion about wrapped tri-chords, it's not
because I've forgotten about them.  It's just that I find no place for them in
the modern piano scale of any size.

Regards,

Del