[pianotech] Restringing at Lower Tension

[David Love]

No problem in theory, though I'm not sure what it will sound like.  Some
loss of power certainly but the tone would probably by a bit warmer, more
fundamental and weaker upper partials.  That might be a problem in the
treble and a very light set of hammers at the upper end would be important
to minimize hammer/string contact time.  When I spreadsheet it the tensions
drop to the mid 140 lb range through most of the tenor and low treble.  In
the upper treble where Steinway tends to drop anyway it drops to the mid 120
lb region.  You'd have to lower the bass scaling as well which you could do
by dropping the wrap dimensions some (I tried .002 - .004" quickly and that
seemed ok) and the core dimension if necessary but a good bass scaler who
can put it all together with the rest would be helpful.    I've often
wondered about this, whether on an old and weakened soundboard dropping the
tensions won't keep things more in balance--well, it would keep things more
in balance but what the tonal result would be I'm not sure.  The problem
here might be that if the impedance characteristics of the soundboard are
too high for the lowered string scale you'll have a mismatch and the sound
will be weak.  If the board is the original one and the impedance
characteristics are lower by virtue of age and diminished crown then who
knows, might be ok.  

David Love
www.davidlovepianos.com


-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of William Ballard
Sent: Wednesday, August 17, 2011 6:37 AM
To: pianotech at ptg.org
Subject: [pianotech] Restringing at Lower Tension

Greetings from a long-time wayfarer.

One of my customers (with nine pianos, most of whom have work by me)  
has a 1892 Stwy AI which he would like now to restring with a new  
block (plus new action). He has a notion (deserving to be tested) that  
if the stringing scale is stepped down a wire size (read: rescale  
entirely, at lower tension), that this will send the sound of the  
piano further in the direction of the "19th Century". ie., The onset  
of the sound will be slightly delayed (IOW, gentler bloom). I've  
explained to him that the place to adjust bloom is with the proper  
choice and voicing of hammers. He realizes that lower string mass  
means lower volume, and although I don't know what size room the piano  
will end up in, I'm sure this is part of his thinking.

A few more details to get the collective wisdom off and bubbling:

1.) The original board is fine (no weak regions, downbearing is there  
along with front bearing at the bridge). This will be the foundation  
for this 19th Century sound. But the rescaling will be stringing  
alone; the tenor bridge and all speaking lengths will not be changed.

2.) I'm turning the action into a high Strike/Balance Ratio action  
with light hammers on 15.75 knuckle-mounting distance shanks. There  
are plenty of choices for light hammers. This will preserve the 19th  
Century feel.

His instincts about pianos are usually right on. (It's me who's  
getting used to the idea of turning a Stwy A into a square grand.)

Bill Ballard RPT
NH Chapter, P.T.G.
wbps at vermontel.net

"I'll play it and tell you what it is later...."
     ...........Miles Davis
+++++++++++++++++++++