S&S D Duplex

[fordpiano@earthlink.net]

> Alas, I am not one of Duplex Dan's experts.

Alas.

> Over the years I have found
> tuned duplex string segments--whether they are
> in front or in back of the
> intentionally speaking string segment--to be
> more trouble than they are
> worth. While 'tuned' string segments toward the
> back of the bridge are less
> troublesome than those in front I have still
> not found them to be of any
> substantive value... 

I've heard good pianos with tuned duplexes, without tuned duplexes, and with
no duplexes at all, both felted and unfelted.  So, it's going to take some to
convince me that a tuned duplex is a necessary part of good piano tone. 
However, I would like to understand more about what they are actually doing so
that this 'feature' could be used knowledgeably by those who want to use it or
who feel it adds something that they want to their piano sound.

> Now, in fairness to Duplex
> Dan, I have not yet attended one of his class
> demonstrations..

Nor have I.  But I plan to when the opportunity presents itself to give him a
chance to convince me.

> Enough to convince myself that the
> real gains are to be found in optimizing the
> efficiency of the soundboard,
> matching it to the stringing scale, supporting
> it well and keeping the
> backscale long enough that it does not unduly
> restrict the motion of the
> bridge/soundboard assembly.

Agreed.  Based on my own listening experience, if tuned duplexes influence the
tone, they do so far less than other design features of the piano.

> I am not at all impressed with any list of
> current (or, for that, past)
> manufacturers who use the system. Or claim to...
> 
> Nor am I frightened by claims that Baldwin's
> demise can be laid to the fact
> that some years ago they abandoned the tuned
> duplex backscale arrangement...

One could just as easily compile a long list of piano manufacturers who used
the 'tuned' duplex scale who are now out of business.  Did I hear someone say
Wisner?

> Unless some correlation can be made between
> that and the past several
> decades of unbelievably bad management.

If management had their heads on straight they never would have abandoned the
tuned backscale. <G>.  If they can't get this right how can they run a
company?

> 
> The major problem I have with this whole tuned
> backscale discussion is that
> it requires thinking of each string (or unison)
> and its associated bridge
> segment as a series of mono-chords
> (mono-unisons?) acting independently of
> each other.

Granted.  But I'm having trouble understanding how one string works.  So I'd
like to get that down before I think about a whole piano.

> The do not, of course, what happens
> to one unison happens also
> to the adjacent unisons for some distance up
> and down the bridge...
> In real life it would be
> pretty difficult to come up with any backscale
> length
> arrangement--deliberately tuned or not--that
> did not have at least a few
> adjacent backscale string segments harmonic
> with some driving string
> segment.

> Del

Good point.  And if all the duplexes are 'tuned', for any given vibrating
string not many of the rear duplexes will be a harmonic of that particular
string.  This may be the reason that we don't hear much if any difference
between pianos with and without tuned rear duplexes.

Phil F