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modulating upright piano damper after-ring

  • 1.  modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 04-29-2023 01:51

    I work on a MH upright, newish, that has an annoying after-ring that clearly emanates from the monochords only.  I'm looking for solutions that folks have found to this issue by installing damper extensions.  There's plenty of force on the strings applied by the damper springs, in fact, more than is desirable in terms of touch characteristics, so it's not that and I'd prefer not to increase that force even if it were to have the desired effect. 

    It may be that the dampers are touching or are near a harmonic node but there aren't any realistic options to moving the dampers.  So the only options seem to be extending the existing dampers by installing longer dampers or adding a damper wire extension (see below).  What have any of you found to be the most effective and if it's the wire extenders where did you get those parts and how did you go about attaching them.  I'm thinking this type of idea though for the monochords (the picture below is for the low tenor),



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    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
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  • 2.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 04-29-2023 08:39

    Juergen had the extenders available through his supply company that Dale Erwin now operates: https://pianofortesupply.com/
    Never seen them on monochords, though! I'd try the heavier brass barrels first, and then different felt &/or configuration of felt pieces.
    Good luck!



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    Patrick Draine RPT
    Billerica MA
    (978) 663-9690
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  • 3.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 04-29-2023 11:38

    Jim Ialeggio demonstrated the effectiveness of adding a little lead weight asymmetrically on to the damper as well. This really quieted things down.

    Peter Grey Piano Doctor 



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    Peter Grey
    Stratham NH
    (603) 686-2395
    pianodoctor57@gmail.com
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    Original Message


  • 4.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 04-29-2023 13:05

    That was for a grand this is an upright



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    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
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    Original Message


  • 5.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 04-29-2023 13:25

    I'll contact Dale.  I don't think I want to "try" things, I'm interested in what people have done that they know works.  I'm pretty sure an extension is the right answer here.  thanks



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    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
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    Original Message


  • 6.  RE: modulating upright piano damper after-ring

    Posted 04-29-2023 18:18

    It will cost very little to wrap a piece of lead wire around a damper head, and you'll get direct information from the piano as to its effectiveness.



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


  • 7.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 04-30-2023 10:17

    While the brass damper barrels are available at pianofortesuppply.com, the "helper" damper extenders (which I bought from Jürgen years ago) aren't listed. Perhaps a direct email to Dale or Jürgen would find a source. The suggestions to try temporary weights (lead wire, clips) are worth a try!



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    Patrick Draine RPT
    Billerica MA
    (978) 663-9690
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    Original Message


  • 8.  RE: modulating upright piano damper after-ring

    Member
    Posted 04-29-2023 20:21

    Are you talking about a damper leak ? I have found that weaving some action cloth through the back scale strings works and that sometimes what appears to be a leak is a sympathetic vibration elsewhere. I tune a very tall Pramberger Signature vertical that has an over damper around the area in your picture and it must be oem design. I would have to look at some pictures I took but a full size vertical August Forster I tuned had (I think) some over dampers. 



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    James Kelly
    Owner- Fur Elise Piano Service
    Pawleys Island SC
    (843) 325-4357
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  • 9.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 04-29-2023 21:25
      |   view attached
    Usually the problem is a lack of mass, not spring pressure -- it's an impedance problem. Two solutions I've used are replacing the wood barrels brass or adding mass in some other way. Lead wire or fishing leads. 

    ddf

    --
    Delwin D Fandrich
    Fandrich Piano Company
    Piano Design and Manufacturing Consulting Services -- Worldwide
    6939 Foothill Ct SW -- Olympia, WA 98512 -- USA
    Phone 360.515.0119 -- Mobile 360.388.6525





  • 10.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 04-29-2023 23:03
    PS. I think small binder clips (office supply) will fit over most wood barrels if you want to try adding mass without changing barrels. It's been years since I've done this so I don't remember the details. But it did make a difference. I don't remember what they weighed. 

    ddf

    --
    Delwin D Fandrich
    Fandrich Piano Company
    Piano Design and Manufacturing Consulting Services -- Worldwide
    6939 Foothill Ct SW -- Olympia, WA 98512 -- USA
    Phone 360.515.0119 -- Mobile 360.388.6525



    Original Message


  • 11.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 04-29-2023 23:07
    PPS. I usually installed brass barrels through the whole bass section. The bi-chords are not as problematic given the wedging of the damper felt. But the damper head still ends up wobbling around a lot. 

    ddf

    --
    Delwin D Fandrich
    Fandrich Piano Company
    Piano Design and Manufacturing Consulting Services -- Worldwide
    6939 Foothill Ct SW -- Olympia, WA 98512 -- USA
    Phone 360.515.0119 -- Mobile 360.388.6525



    Original Message


  • 12.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 04-29-2023 23:25
      |   view attached
    PPPS. I published an article in the Journal about this, lo these many years back. If this forum will accept a PDF file, here it is.




    Attachment(s)

    pdf
    03 Dampers.pdf   181 KB 1 version
    Original Message


  • 13.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 04-30-2023 02:42

    It's not a leak or a wobble or even a slow or inconsistent shut off. I believe it's a harmonic node issue as the ringing continues for several seconds before it finally, and slowly, dissipates. Therefore I don't think mass is the answer.  I think it's a design problem relating to the location of the dampers in that section. The problem is only with mono chords and pretty much all of them.

    The answer, I believe, would be to move the damper so it's not on or near the node but since that's not so easy to do on an upright, a damper extension seems to be the logical solution. 

    I'll report back once I've addressed it. The location of piano is such that I don't want to make more than one trip to resolve this if possible. 



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    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
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    Original Message


  • 14.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 04-30-2023 07:45
    David

    My first instinct was to move the damper up or down, as you alluded to. I've done that on several occasions with good results. It does take much, as little as 1/4". Lowering all the dampers in a section that much will still give you a nice straight line. 

    Wim



    Original Message


  • 15.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 04-30-2023 08:12

    I also had this issue on a tall Pramberger. However, after discussing it with the owner it was decided that they were not bothered by it (only I was), hence we did not attempt any "fixes". 

    Peter Grey Piano Doctor 



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    Peter Grey
    Stratham NH
    (603) 686-2395
    pianodoctor57@gmail.com
    ------------------------------

    Original Message


  • 16.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 05-01-2023 07:52
    David,

    Baldwin 52" upright had four-piece felt dampers. they were longer than 
    any I had seen; however the length was not the primary reason they worked
    so well, although it no doubt contributed to the damping efficiency. 
    The placement of the felt was the most significant factor in cancelling nodes.

    You might try to fabricate some new ones rather than trying to McGuyver 
    the existing heads.  



    Original Message


  • 17.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 05-01-2023 16:59
    The Baldwin 52" upright also has an unusual hammer strikepoint -- one-fifth at A-1 (if memory serves). 

    ddf

    --
    Delwin D Fandrich
    Fandrich Piano Company
    Piano Design and Manufacturing Consulting Services -- Worldwide
    6939 Foothill Ct SW -- Olympia, WA 98512 -- USA
    Phone 360.515.0119 -- Mobile 360.388.6525



    Original Message


  • 18.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 05-01-2023 10:41
    David, can you identify the pitch of the after ring? That might help decide if a damper edge is resting on a node. Sometimes it’s possible to change the configuration of the damper sections if the whole damper can’t be moved to a better location.

    Bob Anderson, RPT
    Tucson, AZ


    Original Message


  • 19.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 05-02-2023 08:34

    Dave C

    i may try that. Thanks

    Roberts A

    i did not identify the exact harmonic but will when I return. 



    Thanks all for the input. I have some ideas and will report back after I revisit. 



    ------------------------------
    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
    ------------------------------

    Original Message


  • 20.  RE: modulating upright piano damper after-ring

    Member
    Posted 04-30-2023 11:06

    May I ask what Model this is on?



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    Zackery Hardy
    Elk Grove CA
    (916) 531-5150
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  • 21.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 04-30-2023 13:31

    Zackery,

    My records show PV-131.  Appears to be replaced by PV-132 currently. 

    Peter Grey Piano Doctor 



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    Peter Grey
    Stratham NH
    (603) 686-2395
    pianodoctor57@gmail.com
    ------------------------------

    Original Message


  • 22.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 04-30-2023 16:40

    Not sure the model but 52" probably 10 years old



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    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
    ------------------------------

    Original Message


  • 23.  RE: modulating upright piano damper after-ring

    Registered Piano Technician
    Posted 04-30-2023 21:23

    Aren't the dampers on those models the long ones with 3 felt blocks? If your surmise is correct that the problem involves touching a node, perhaps the middle or bottom block could be trimmed or removed to avoid the node if you can locate it. Or perhaps replacing a block with a less dense treble felt block.
    I understand your desire to solve this in one trip but this kind of problem can be vexing. The wire extenders aren't a guarantee either. I had a similar problem with dampers last summer, it wasn't a profitable venture for me. >:P



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    Steven Rosenthal RPT
    Honolulu HI
    (808) 521-7129
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    Original Message


  • 24.  RE: modulating upright piano damper after-ring

    Posted 04-30-2023 21:43

    Dealing with one of the longest tenor breaks of any piano, I started with having to make 4 over dampers. But through much tweeking I was able to eliminate 3 of them and was left with one, which was from a node problem. To make the over damper is easy- bend music wire to shape with a loop at the top to sandwich the back of the damper head with another piece of felt.



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    Chernobieff Piano Restorations
    "Where Tone is Key"
    Piano Designer and Maker
    Designer of Inertia Touch Wave
    865-986-7720 (text only please)
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    Original Message