PianoTech Archive

  • 1.  Restringing at Lower Tension

    Posted 08-17-2011 07:37 
    From William Ballard <yardbird@vermontel.net>

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@vermontel.net

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


  • 2.  Restringing at Lower Tension

    Registered Piano Technician
    Posted 08-17-2011 08:31 
    From "David Love" <davidlovepianos@comcast.net>

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



    
                                                
    
					
                                                    

        
                                                
				
    
                                                
    
                                                    
                                                        
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  • 3.  Restringing at Lower Tension

    Posted 08-17-2011 11:05 
    From "Encore Pianos" <encorepianos@metrocast.net>

Mr. Bill:

This has potential to be a sticky wicket with your customer, your long time
trusting relationship with him notwithstanding.  He will be spending many
thousands of dollars to achieve a particular result, which may or may not
disappoint him.   It's 50 -50 as I can see it.  Even though it is his choice
you can still get blamed - you should have known enough to protect me from
myself, although he won't think of it quite in those terms.  Or some people
might think it is a bad rebuilding job on your part, and how would they know
anyway?

As David points out below, there are some potential problem areas.  Here's
my suggestion:  Since the piano is to be rebuilt anyway, ask him to allow
you to restring several notes at the stepped down wire size.  The problem
areas are the best choice, say the last plain wire in the low tenor where
the tensions are falling off anyway and would be most likely to develop
tonal warts from this change, and in the upper treble area of which David
speaks.  Space 2 or 3 notes in between.  

The advantage of this method is that you are only changing one thing, the
wire sizes.  No downbearing changes or any of the other vagaries that come
with pulling a plate and putting it back in.  No new hammers and the tonal
changes they bring.  The new wire will sound sweeter, but will it otherwise
be diminished in tone color by the lower tension?  He'll pay you for your
time, and it's as close to apples to apples as we can get.  If he decides to
go ahead then, the onus is fully on him and your back is covered.  If he
does not like it, you saved him thousands of dollars and disappointment, and
your relationship is preserved.  

Will


    
                                                
    
					
                                                    

        
                                                
				
    
                                                
    
                                                    
                                                        
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  • 4.  Restringing at Lower Tension

    Registered Piano Technician
    Posted 08-17-2011 13:11 
    From "Delwin D Fandrich"


  • 5.  Restringing at Lower Tension

    Posted 08-17-2011 13:48 
    From "Encore Pianos" <encorepianos@metrocast.net>

Thanks for the correction, Del.  Having read your previous post, I think
that your idea is a far better way to approach it.

Will


    
                                                
    
					
                                                    

        
                                                
				
    
                                                
    
                                                    
                                                        
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  • 6.  Restringing at Lower Tension

    Registered Piano Technician
    Posted 08-17-2011 13:05 
    From "Delwin D Fandrich"


  • 7.  Restringing at Lower Tension

    Posted 08-18-2011 10:19 
    From William Ballard <yardbird@vermontel.net>

Thanks to all who replied yesterday. The project sounds quite  
promising, and once again confirms as sound, the instincts of my client.

On Aug 17, 2011, at 3:05 PM, Delwin D Fandrich wrote:
> If you do not wish to do the actual rescaling work you might consider
> working with a technician already experienced in the process. Your  
> client's
> desires are not all that unusual--a good share of the pianos I  
> rebuild these
> days end up with string tensions that are somewhat lower than the  
> originals.
> The results you client wants are not impossible to achieve. But for  
> the best
> results I'd strongly recommend that you actually measure the speaking
> lengths and work up an appropriate scale based on those measurements.

I've never done any scaling (although familiar with the basic  
concept), nor have I learned to use a sewing machine. So it will be  
done by someone who knows how.

Del, can this job be done simply on the basis of speaking lengths  
entered and formulae executed? (ie., by mail?) Or would the best job  
involve judgement calls, based on

1.) the rescaler being in the same room with the piano before tear- 
down, and/or
2.) the rescaler having in their experience one or more Stwy AI  
rescales?

This is the second 100+ year Stwy A I've dealt with for my client, in  
which the board had crown even (no trough under the bridge), front and  
back bearing at the bridge was fine, and the piano had nice sustain  
throughout (no weak octaves) even listening through 100yo materials.  
The first, a 1906 AII which I restrung with a pinblock, came out very  
strong, even when retaining the original hammers. In fact the initial  
sound of the fresh wire and original hammers was VERY bright. This  
maybe the reason he want to lower tension on the AI.

> Don't worry about turning the A1 into a square; they are apples and
> pomegranates. The A1 is capable of a smooth and balanced timbre that  
> even
> the best square could only dream about.

My sense of humor expressing nervousness about the idea. If he asked  
to turn the piano into a square grand, the first thing I'd do is to  
separate the board from the belly rail and let it flap in the breeze.

> You're right about the hammers. They will need to be relatively  
> light to
> avoid overpowering the scale. You'll also want something without a  
> lot of
> density.

David Love (among others) has made this point over the years. I was  
mainly interested in what the high action ratio would offer (greater  
magnification of the velocity range a pianist can apply at the front  
end).

Hmmmm? light and big (lots of air space between fibers). Like an Isaac  
(though he no longer appears in the Directory)? Density can be  
adjusted during the voicing, and there are plenty of light hammer sets  
around. (Among them, I'd  choose an Abel.)

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


  • 8.  Restringing at Lower Tension

    Registered Piano Technician
    Posted 08-18-2011 11:48 
    From "Delwin D Fandrich"


  • 9.  Restringing at Lower Tension

    Registered Piano Technician
    Posted 08-18-2011 20:39
      |   view attached 
    From "David Love" <davidlovepianos@comcast.net>

I have to agree with Del here on the hammer choice.  Considering the board
is probably a bit weak and prone to some percussive tendencies and add the
lighter gauge strings and therefore less downbearing and a lowering of the
impedance I think you want to be careful using a hammer that is too hard.
Since the action ratio dictates a light hammer anyway that works out because
I think you'll be best with one, especially in the treble section.  Lower
tension (if that's the route you go) will increase hammer string contact
time and reduce partial development.  So light and not to hard will serve
this project well, I would think.  Bacon or a light set of Weickert hammers
if you want to go a bit firmer.  Del's also right that a complete assessment
of the scale even if you aren't changing the speaking lengths can serve to
clean things up some, get the tensions and other factors more in line with
each other and get a batter balance.  

 

While we're on this subject I tuned a small Fuerich grand today (172 cm).
It's really a beautifully made piano but, IMO, the scale tensions are simply
too high.  To give an idea, in the treble section, C88, 52 mm and 13.5
gauge, note 73, 112 mm 15 gauge puts those tensions up in the 170 lb range.
But worse it's a highish tension achieved largely by string diameter (more
than length).  It creates a much harder and edgier sound up there that you
just can't voice out.  If you soften the hammers it get dull and harsh
rather than bright and harsh, if that makes sense-like putting Steinway
hammers on an old Yamaha.  The board seems to be pretty light just from a
cursory look at the ribbing (which means a bad match possibly).  There's
plenty of backscale (and a nice laminated cap as well).  Bass relationship
to tenor is nice, 29 note bass with 13 monochords, long backscale, though
the scaling is a bit weird, some inharmonicity problems evident with how it
tunes.  Might be the shape of the bridge was done to match the plate rather
than the other way around.  More likely just poor diameter choices.  But in
fairness, I haven't analyzed it.  

 

Anyway, point being that here's a piano that, in my opinion, could be really
nice if the scale were lighter and more balanced with the soundboard (and
the hammer along with it) and is a good example of getting two of the three
things coordinated (scale and hammer) but the board weighting is for
something else-maybe. Again, I've not analyzed it, just reacting to what I
hear.  At $75,000 new, however, I'm not suggesting that to the customer.  

 

(BTW, nice to be able to cut and paste a picture here, even though it won't
make it to the archives)  HTML required for this viewing.   

 

David Love

www.davidlovepianos.com

 

 



 

 

 

 

 

Hmmmm. light and big (lots of air space between fibers). Like an Isaac

(though he no longer appears in the Directory)? Density can be adjusted

during the voicing, and there are plenty of light hammer sets around. (Among

them, I'd  choose an Abel.)

-----

 

      Personally, from what you've written about the desired timbral goals

for this piano--and assuming a suitably light scale--I'd be looking at

something like a cold-pressed Ronsen with Bacon felt. 

 

ddf