A tenor bridge conversion

[Ron Overs]

Hi Stéphane,

Its an interesting question you raise. I often 
wonder why they've suffered it for so long also. 
I would have ditched it in an instant, but I 
don't work in a hierarchical structure, and I 
don't have a history to respect. I suspect that a 
lot of the problem for a major factory with an 
illustrious past is that were they to make major 
changes to the design, people would automatically 
ask what was wrong with the previous design? 
While ever you change nothing, you don't have to 
admit that anything is wrong, even if it doesn't 
work.

I can just imagine what a warm and fuzzy 
reception one might get at the Bechstein factory 
if one of the troops went up to Mr Shulz and 
complained about some aspect of the design. In 
2005 when we exhibited our action on the Gold 
Coast, Carl Shulz attended the show. He called by 
the booth where our action was being demonstrated 
and had a look at the Overs action model. He took 
a very brief look at it, threw his eyes skywards 
as if to imply, ". . . what an idiot", and walked 
on. Yes, I can just imagine how new thinking 
would be 'eagerly' encouraged at the Bechstein 
camp.

I also believe that for many companies there are 
almost traditional points at which the bass 
treble sections cross. For example, in the S&S B 
the holy grail cross point is E20/F21. This scale 
is, compared to the Bechstein C, a better result, 
since the B's F21 length is around 147 cm (on the 
model C the low break note for the treble was 
135.2 cm at note E20). But it still doesn't work 
when compared to the option of taking the break 
to a higher point.

When pulling S&S Bs down for a rebuild, just to 
have a listen I've pulled F21 up to Bfl26. The 
tone is very much superior, and the break 
percentage is still only at 42%. Of course 42% is 
getting moderately high for the tri-chords, 
because we'd need to take the bi-chord covers on 
the high end of the bass bridge up to around 54% 
to balance the Z, but even that's doable.

I believe the reason that the B breaks at F21 is 
because that is where the D breaks. It doesn't 
work from a musical and tuning stability 
perspective, but I'll bet that it does from a 
political standpoint.

Ron O.

>Hi list, hi Ron.
>
>Just one stupid question for Ron.
>Ron, I truly appreciate your work and effort in piano improvement.
>But reading this, one question comes to my mind :
>do you really believe that Bechstein engineers 
>were not aware of the % of breaking strength of 
>the tenor strings of their pianos ?  I suppose 
>not.  So the next question is : why the hell 
>those educated people did chose to implement 
>such a design (the tension drop in low trebble 
>bridge) on such an expensive piano ?
>Just wondering.
>
>Best regards.
>
>Stéphane Collin.
>
>----- Original Message -----
>From: <mailto:concertpianoservice at planet.nl>Concert Piano Service
>To: <mailto:pianotech at ptg.org>Pianotech List
>Sent: Monday, January 22, 2007 8:40 PM
>Subject: Re: A tenor bridge conversion
>
>
>On 22-jan-2007, at 1:52, Ron Overs wrote:
>
>>Hi all,
>
>I've just loaded a couple of images onto my 
>webspace which show the layout for a tenor 
>bridge conversion of a Bechstein model C grand, 
>and an image of the new tenor bridge in place 
>prior to stringing.
>
>Here is an image link taken at the layout planning stage;
>
><http://members.optusnet.com.au/ronovers/bech_c_tenor1.jpg>http://members.optusnet.com.au/ronovers/bech_c_tenor1.jpg
>
>Here is an image link, taken last Friday which 
>shows the finished tenor bridge in place, 
>awaiting strings.
>
><http://members.optusnet.com.au/ronovers/bech_c_tenor2.jpg>http://members.optusnet.com.au/ronovers/bech_c_tenor2.jpg
>
>The original Bechstein C (circ 1953) was one of 
>the most outstanding examples of a poor scale 
>I've ever measured in a mid sized grand. The 
>tension dropped down to around 18% at note E20 
>(the lowest note on the long bridge). To rectify 
>this problem, a new tenor bridge was designed 
>from the first original trichord plain note, 
>E20, up to note D#31. The new lowest 
>plain-strung trichord is at a respectable 
>tension of 36%. This will transform the model C 
>from one of the worst crosses in the business, 
>improving it to the point where it is about 
>equivalent to the cross of a model D Steinway 
>(in terms of percentage of tension deviation - 
>the lower the deviation the better the tuning 
>stability). Should have it strung and playing in 
>a couple of weeks.
>
>Ron O.
>
>
>
>
>Hi Ron,
>I have a question :
>
>You cut off the treble bridge in the tail. Did 
>you do that because that last part of that 
>treble bridge is so close to the rim?
>I worked on a brand new Bechstein C and I 
>noticed that those first treble notes (nr 21 to 
>appr. nr 30 sounded weird and were difficult to 
>voice correctly, as usual).
>I also wonder what kind of string thickness you 
>use on that new bridge you built. Do they get 
>thicker in size because they are shorter?
>
>
>friendly greetings
>from
>André Oorebeek
>
>Antoni van leeuwenhoekweg 15
>1401 VW Bussum
>the Netherlands
>
>tel : 0031 35 6975840
>tel : 0031 652388 008
>
>where music is,
>no harm can be


-- 
OVERS PIANOS - SYDNEY
    Grand Piano Manufacturers
_______________________

Web http://overspianos.com.au
mailto:ron at overspianos.com.au
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