[pianotech] question about agraffes and uprights

[Roger@Integra.net]

Euphonious,
Yamaha’s U5 agraffes are used as the termination of the speaking length.
Roger Gable

From: Euphonious Thumpe 
Sent: Saturday, February 09, 2013 10:50 AM
To: pianotech at ptg.org 
Subject: Re: [pianotech] question about agraffes and uprights

      Another point about agraffes, of course, is that the arched surface of the hole interior mates better with the string roundness than a flat surface. (So, I'm guessing, less propensity to vibrate loosely against it and "zing".) My comment about capos was merely meant to discuss reflectivity. No other factors. As Ron said, there are "too many variables" in this situation (relative hardnesses of capos, agraffes, string lengths and tensions, etc.) at least for my small brain to cope with. So be it.

      Thumpe.

      P.S. I've worked on only old stuff. Does the U-5 use agraffes for speaking length terminations, or are they above an upper plate bridge? 



--------------------------------------------------------------------------------
From: Roger at Integra.net <rgable at integra.net>; 
To: <pianotech at ptg.org>; 
Subject: Re: [pianotech] question about agraffes and uprights 
Sent: Sat, Feb 9, 2013 4:40:29 PM 

      Ron,
      I was one of those technicians who tried using water hardened drill rod as a bridge pin because of the almost unlimited sizes available to reduce the amount of "drill out" of the bridge cap to facilitate the next larger size. Ed McMorrow  told me that he experienced the same zing years ago. You are correct to mention the many variables into the piano design that dictate the qualitative aspects of piano tone, thus my mention of those that might want to pick apart my explanation -- just too many variables -- and spot on with your comments of the low quality without and the good quality uprights.

      Euphonious,
      The Yamaha U5 upright use agraffes throughout the scale.

      Roger Gable

      -----Original Message----- From: Ron Nossaman
      Sent: Saturday, February 09, 2013 8:02 AM
      To: pianotech at ptg.org
      Subject: Re: [pianotech] question about agraffes and uprights

      On 2/8/2013 6:00 PM, Roger at Integra.net wrote:
      > Certainly, it is known that if you install a hard bridge pin
      > made of water cooled drill rod, you will hear a zing in the string
      > especially in the mid to lower sections; so hardness of the
      > terminations are important.

      Is it? I confess I've never tried it, nor run across it. String
      termination zings I've encountered have always been from inadequate
      bearing or pin angles. I know Ron Overs is a big fan of hardened
      terminations, and routinely electroless nickel plates agraffes to harden
      the termination surface. He has also custom made steel agraffes to get
      as hard and rigid a termination as he can. He flame hardens capos as
      well. His pianos are as clean sounding as anything I've heard.


      > Now let’s see how the flood of
      > comments or counter comment picks this apart, especially those that
      > claim that the lower quality grand pianos with no agraffes sound
      > “fine” and the good quality uprights without agraffes sound great.

      To me, lower quality grands without agraffes sound like lower quality
      grands, and good quality uprights tend to sound like good quality
      uprights if the voicing is decent. I can't blame either on the presence
      or lack of agraffes. There are way too many other variables.
      Ron N 
     
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