Front Duplex

[Duplexdan@AOL.COM]

Kevin,

Your report of your treatment of the front duplex in a S & S M is most 
interesting and challenging. Although I've spent many years developing duplex 
tuning technology, 98% of it has been on rear duplexes so I don't know how 
valuable my comments may be to you. However in the interest of your client's 
satisfaction and our edification I'll offer a few thoughts hoping that 
perhaps one on them may be useful.

The "proper fix" should be when the duplex scale of that particular unison 
produces a fundamental tone which is a partial of the speaking length. The 
front duplexes are pretty short, so they're way up there, e.g. triple 
octaves. Since front duplexes are for the most part nonadjustable you may 
have to resort to muting if no other solution can be found. The fact that the 
disturbance occurs, however, on only a few notes suggests that the problem 
may not be the duplex at all.

The appearance of the problem after the piano was tuned is really the only 
time when the duplex effect can be perceived. Everything else has to be 
correct. It is a finishing touch to the tone. "All the other stuff" must be 
in place, strike point, bearing, hammers, strings, etc. before the subtlety 
of the duplex effect can create the "singing tone" Steinway speaks about in 
his patent. 

Your mention of the phrase " long waste end notes" may be misleading. Nothing 
is really wasted. The lengths of string beyond the agraffes are not really 
wasted, otherwise we would be terminating strings at the bridge pin, and that 
doesn't work in even the smallest ukelele. It may not seem physically 
possible at first thought, but the string is totally alive from hitchpin to 
tuning pin. There is life after the agraffe. Exactly how much, I can't say 
but the longitudinal waves produced by the striking of the hammer on the 
string are affected by the distal portions of the string, the non speaking 
lengths which you refer to as "waste". Personally I don't think there is any 
waste. 

In my view the actions of seating the strings was exactly on the money. The 
result of doing some needling on the crown, which had an ameliorative effect 
suggests that voicing may be the answer.

I don't blame you for disliking having to deal with these issues on an 
expensive piano, or for that matter any piano. But until factories who 
manufacture pianos with duplex scales can solve the problem of achieving the 
best sound for their piano by the optimum placement of their duplex scale 
oliquot or contiguous harmonic bridge, we may have to deal with it, just as 
the buyer of a new Mercededs or jaguar has to take his vehicle to his own 
private mechanic to fine tune the vehicle. ( I may be wrong on this because 
I've never bought a new Mercedes or Jaguar)

There is one little anecdote on this subject that you might like to hear. At 
a National Convention some years ago I sat next to a Yamaha technician at our 
Banquet. i had tested the magnificent Yamaha grand in the exhibit, and found 
that the duplex scales were all muted. But after loosening the braids on a 
few unisons i found that the duplex scale was not in tune with the speaking 
length. I asked the yamaha technician why they muted the duplexes. His answer 
was, as well as i can recall:
We don't tune them, we mute them"  Well, Yamaha is selling a great deal of 
great pianos so it may be "moot" to discuss the "mute" . 

Hope this has been of some help. I'd be anxious to hear of your further 
progress in this matter.

Duplexdan@aol.com