Pianotech

  • 1.  loud and thin

    Registered Piano Technician
    Posted 04-01-2025 09:03

    Last summer I replaced the hammers on a Yamaha C7 with Abel hammers. This is in a rehearsal room of a university and the floor is carpeted. To me the piano sounded great, but almost immediately the faculty said the piano was too soft. No power.  A couple of weeks ago I added a generous amount of B72 to the hammers, and the sound came alive. But now the complaint is that while the piano is loud enough, it is also thin and tinny. I need some advice as to how to keep the volume but get rid of the thin and tinny sound. 

    Wim



    ------------------------------
    Willem "Wim" Blees, RPT
    St. Augustine, FL 32095
    Tnrwim@aol.com
    ------------------------------


  • 2.  RE: loud and thin

    Registered Piano Technician
    Posted 04-02-2025 06:05

    HI Wim,

    Sounds like (ha!) the hammers are missing an essential element which is soft felt at the surface for pianissimo quality which in this case seems to be lacking.  Aggressive sugar coating is needed.  Traditional thin shallow needles won't do it.   Compass point needling at the right pressure is worth a try.  Compass point voicing needle have an inclusive angle of about 13 degrees. Start with a sample note.  Light pressure straight down all over the strike surface.  Listen...   Keep increasing pressure until the sound starts to bloom.  Once your confidant about the right amount go for it across the sections.  Following with a ball peen hammer can help soften and work the fibers into more flexibility at the surface.

    Many years ago at one of the national conferences I demonstrated replacing a hammer around C5 with a solid hard rubber hammer of the same strike weight as adjacent notes.  It was a Yamaha grand.  I slid in the action and played the note.  The audience gasped!  So did I!  It sounded better than the felt hammer!   But wait.  When I played forte the tone sat down and said "NO!"    No core hardness...  When I played into the pianissimo range the tone became thin and tinny.  No surface softness.  I stretched a piece of bushing cloth over the top and the Pianissimo tone bloomed without detriment to the MF tone.    The hard rubber

     with no gradient in hardness the tone only sounds best at one dynamic.

    Piano hammers need a gradient of density for good tone at all dynamic levels.   Lacquering tends to make the felt hard from surface to deep.  No gradient.  Hammer weight levels have a huge influence. The lighter the hammer weight level the deeper the gradient needs to be.  Light hard surface hammers are the devil. 



    ------------------------------
    David Stanwood
    stanwoodpiano.com
    stanwood@tiac.net
    508-693-1583
    ------------------------------

    Original Message


  • 3.  RE: loud and thin

    Posted 04-02-2025 12:16

    A couple points. Wrong technique and wrong chemical.  What i call fortissimo voicing should be done from the side and basically avoid the attack area. You have to pull the action and stand it up, so the sides of the hammers are exposed. B-72 is great for brightening the attack area without creating a ping like lacquer does. But its too soft for fortissimo voicing. Besides because of its softness you need to apply way too much , and by the time it becomes effective, it gumms up the felt. I use diluted sandarac (hardest alcohol solvent resin) for fortissimo voicing and very little is required to hear a difference. Once fortissimo is taken care of, the attack usually require a little B-72 only.

    I enjoyed our lunch together very much!~ It was nice meeting you!

    Take Care,

    -chris



    ------------------------------
    Chernobieff Piano Restorations

    Inventor of Inertia Touch Wave (ITW)
    Advanced Resonant Compression Engineered Soundboards (ARCHES)

    865-986-7720 (text only please)
    ------------------------------

    Original Message


  • 4.  RE: loud and thin

    Posted 04-02-2025 13:25
    Abel hammers really should be played in, just played. They are soft to begin with, but play in nicely. Once played in, then sand level to take off the raised edges. Then potentially treat bass with paraloid to give power to bass and mate with strings.

    The effect is slow but patience is rewarded. 

    Early treatment with paraloid might not have been the best approach.

    One of the problems is that an organisation expects a piano as a predictable object and opon which changes should be instantly achieved. The reality is that the best instruments are alive, living beings, which develop their qualities over time.

    Some recordings document the progress of an instrument with Abel hammers over time.

    The Hammerwood Bechstein had refelted hammers by Abel in 2012
    A direct comparison between the old hammers https://www.youtube.com/watch?v=7JF3YzTG7lU 
    and the new in 2013 https://www.youtube.com/watch?v=XU-ilRBeZ84 (amusing comments by a French tech who apparently was having a difficult time)



    At some stage I sanded the hammers flat with improvement of tone but don't recall when
    https://www.youtube.com/watch?v=Hp6-GtXNa6A was two years ago after paraloid on bass and mating of hammers on strings
    https://youtu.be/HSiZ2ilGY-4?t=302 and https://www.youtube.com/watch?v=aIVUyu7v48U was last summer after paraloid on bass, restringing
    https://youtu.be/9fvJ_8DtDwk was after strenuous exercise with Rachmaninoff 2

    Are changes of the hammers audible despite hearing them through potential improvements of microphones and recording?

    Best wishes

    David P


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



    Original Message