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Lost crown at treble end of soundboard on historic piano. Any remedy?

  • 1.  Lost crown at treble end of soundboard on historic piano. Any remedy?

    Posted 23 days ago
    After restringing an 1869 Broadwood Cottage grand - bicord in centre and trichord in top treble, the top treble is near untunable with false notes on every string. It's been puzzling me.

    The instrument gives a good account of itself
    Handel, Kulau and Carl Maria von Weber - flute, piano and cello trio
    YouTube remove preview
    Handel, Kulau and Carl Maria von Weber - flute, piano and cello trio
    NOTE: all these composers died more than 100 years ago. Any copyright claims are fraudulent by the claimants. 1869 Broadwood Cottage Grand piano tuned to Kir...
    View this on YouTube >

    but that top treble should be as clear as a bell.

    Examining the instrument the bridge has sunk and the sounboard is depressed in the tricord area, probably on acount of the 1/3 higher downwards force.

    Is there any way perhaps with loosening tension and applying steam and force from underneath that perhaps one might be able to restore the shape of the crown?

    I'm guessing that without a proper crown giving a resisting force, vibration of the string moves the soundboard in a manner that changes the string tension depending on whether the string is up or if it is down, so therefore providing two tensions to the string and therefore two resulting notes.

    In PTG posts in living memory issues of string twisting when stringing have been explored, and the strings are well mating with the bridge and bridge pins.

    For anyone interested in the recording quoted above by the way, Kirnberger III temperament is in use here.

    Best wishes

    David P



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    David Pinnegar BSc ARCS
    Hammerwood Park, East Grinstead, Sussex, UK
    +44 1342 850594
    "High Definition" Tuning
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  • 2.  RE: Lost crown at treble end of soundboard on historic piano. Any remedy?

    Member
    Posted 23 days ago
    DId you recap the bridge, re-set bridge height, and repin. Without these actions, restringing is a waste of time, most of the time. Your false beats will be coming from old pin terminations, which are just too mushy to be functional.

    Over the last 5 years, I have proven in numerous instances, that, given the proper diagnostics, a new cap and pins, and proper scaling, boards without crown can perform quite musically. Glue joints absolutely must be proven to be adequate, both at the rim and along the full lengths of the ribs. But the biggest bang for the buck comes from the new cap. Strings alone will not get you there.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 3.  RE: Lost crown at treble end of soundboard on historic piano. Any remedy?

    Posted 23 days ago
    Thanks so much.

    The old strings were 150 years old so restringing was clear.

    Thoughts on recapping are very much appreciated.

    Many thanks

    Best wishes

    David P

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    David Pinnegar, B.Sc., A.R.C.S.
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    +44 1342 850594





  • 4.  RE: Lost crown at treble end of soundboard on historic piano. Any remedy?

    Posted 22 days ago
    Be careful the wire you choose. The breaking strength of wire was different before the Bessemer Blast furnace. Piano wire was of the finest steel and so the Worlds Faire had it as a competition. After the blast furnace the breaking point went up 100 psi.
    Changing to the newer wire will add tension to the plate if you scale it with the modern formulas.
    More tension across the plate and it will bend in half. Especially since if it's a flat plate. That would cause the bridge to go goofy.
    Paulello does historic wire.
    Like Jim says, do the cap.





  • 5.  RE: Lost crown at treble end of soundboard on historic piano. Any remedy?

    Registered Piano Technician
    Posted 22 days ago
    Hi Jim,

    You mentioned in your reply that "glue joints absolutely must be proven to be adequate, both at the rim and along the full lengths of the ribs."

    I have  seen you and others mention this at other times.

    What is the best way to prove they are adequate?

    TIA
    Daniel

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    Daniel Achten
    Chattanooga TN
    423-760-2458
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  • 6.  RE: Lost crown at treble end of soundboard on historic piano. Any remedy?

    Posted 22 days ago
    Crown can be restored, but the board must be removed from the piano, shrinkage/cracking must be taken up with strips of wood and the ribs glued back on in a press the same as when it was made. However it sounds like you may have put too much tension on the instrument. What type of wire did you use? On a piano of that vintage you need to re-scale with lower BP wire or it can sound very bad. If you used larger diameters than the original this could damage the piano. 

    --
    "For I am not ashamed of the gospel, for it is the power of God for salvation to everyone who believes." -Romans 1:16





  • 7.  RE: Lost crown at treble end of soundboard on historic piano. Any remedy?

    Registered Piano Technician
    Posted 22 days ago
    How is the soundboard grain oriented to the bridge and case?
    Earlier Broadwoods had the soundboard grain running across the bridge, side-to-side in the case, about 90 degrees off from modern practice.
    I don't know if soundboards built that way ever had crown.
    I don't know when Broadwood changed their soundboard design.
    This piano needs the attention of someone with special experience and knowledge.

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    Ed Sutton
    ed440@me.com
    (980) 254-7413
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  • 8.  RE: Lost crown at treble end of soundboard on historic piano. Any remedy?

    Posted 14 days ago
    Ed- thanks and I will take photos. These pianos are musically very interesting and familiarity with them might lead to them being better appreciated. 

    https://www.youtube.com/watch?v=PmuVipZMmK0 are extracts from a recent concert where the instrument gives a good account of itself.

    It's possibly easy to think that the sound isn't as resonant as a modern instrument but instruments like this need a different from modern pedal technique using the sustain much more freely than people are accustomed to. Then they sing and the non-equal tuning prevents confusion of sound. In not understanding this instruments of  this genre can be dismissed as bad pianos and wrongly so.

    I need to turn it upside down again for a second CA treatment to the pinblock: currently a feather touch is needed on the tuning lever to put it in tune or out, a number of pins on the point of slipping, so this combined with a temperature shift between tuning and mid-concert led to the unisons being not my normal standard of tuning. For Mozart however, it's not a Steinway not is meant to be. Does it have that woody spirit of a Walter or a Stein? 

    Best wishes

    David P

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    David Pinnegar, B.Sc., A.R.C.S.
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    +44 1342 850594





  • 9.  RE: Lost crown at treble end of soundboard on historic piano. Any remedy?

    Registered Piano Technician
    Posted 14 days ago
    David-
    I believe most of us have concluded that there is no advantage, and possible disadvantage to inverting the piano for CA treatment.
    If it's possible to apply CA from the top, it is usually quite effective.
    The late Ron Nossaman, and Yamaha, have made pinblocks with a layer of harder wood laminate on the top, arguing that it is preferable to have greater torque at the top of the pin rather than at the bottom.

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    Ed Sutton
    ed440@me.com
    (980) 254-7413
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  • 10.  RE: Lost crown at treble end of soundboard on historic piano. Any remedy?

    Registered Piano Technician
    Posted 13 days ago

    Very pleasing ambience, very suited to the music.






  • 11.  RE: Lost crown at treble end of soundboard on historic piano. Any remedy?

    Member
    Posted 13 days ago
    Have you considered Fandrich Riblets?

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    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
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  • 12.  RE: Lost crown at treble end of soundboard on historic piano. Any remedy?

    Registered Piano Technician
    Posted 13 days ago
    Here is a photo of Darrell Fandrich riblets.
    Note the slight concavity of the flat surface.
    They are meant to be attached under the soundboard, screwed into the bridge, in between the full ribs.
    The purpose is to add stiffness to the bridge-soundboard structure. The added impedance can reduce the impact sound and add sustain.
    Drill a small hole from below into the bridge and attach the riblet.
    If it helps, leave it. If not, unscrew it leaving a small hole in the bottom of the soundboard.
    Darrell is deceased, but I believe you can buy riblets from the family company. http://fandrich.com


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    Ed Sutton
    ed440@me.com
    (980) 254-7413
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