psycho-acousti-what?

[jolly roger]

Hi Mark

            With the low sustain two things come to mind. Has the board
lost it's crown?  Using a dail type bearing gauge, check to see that you
have .010- .015" of down bearing.  Adjust the acujust  if the board is
good.  If the bridge pins are loose you can also get that pingy low sustain
tone.
Regards Roger



At 07:27 PM 2/13/01 -0600, you wrote:
>Your replys are helpful in clarifying the problem.
>
>Rotating my head (no, not 360 degrees) makes the problem disappear.
>
>The hollow heads (I presume you were referring to the hammers,
>Newton!)sounds plausible.
>
>Switching hammers around, how could I forget to do this!?
>
>Moving the piano(s) does not provide a difference;
>two different pianos, two very different rooms/same sound.
>
>Have single needled through between crown and molding,
>leads me to believe this effect (loud bong/no sustain)has nothing to do with
>the hammer-felt whatsoever.
>
>Ths sound is distinctly "point source and directional." It comes right from
>the area of the scale in which you are playing, and if your right ear is
>angled towards the piano,.."wham!"
>
>The phenomenon is not subtle, and is apparent in individual notes as well as
>intervals.
>
>Again, the idea of a glue hollow in the hammerhead(s)may fit. It also
>suggests why two pianos of the same mfg. and vintage share the problem.
>Especially knowing how this factory (and again, not to criticize) prepares
>the butt end of the shank for glueing.
>
>More ideas are welcome, I will see this piano again within the next two
>weeks to test them out.
>
>So nice to troubleshoot as a "team!"
>
>best regards,
>Mark Cramer,
>Brandon University
>
>
>
>----Original Message-----
>From: owner-caut@ptg.org [mailto:owner-caut@ptg.org]On Behalf Of Mark
>Cramer
>Sent: Tuesday, February 13, 2001 2:52 PM
>To: caut@ptg.org
>Subject: psycho-acousti-what?
>
>
>A year ago, a client told me she had several notes on her (Baldwin) console
>that physically hurt her ear when she played them.
>
>I tried the notes, which were the first few above the tenor/treble break,
>and noted they were a bit harsh, but thought (to myself) maybe she was
>exagerating a bit.
>
>I tried them as major thirds, which she had been playing, and nothing. Then
>I turned my head a bit in her direction, played them again, and "Ouch!" It
>was as though someone was pressing their finger between my upper jaw-bone
>and ear!
>Definitely painful!
>
>I remember trying every bit of "voicing voodoo" I know, to no avail. Indeed,
>I had forgotten about this til yesterday. A music teacher with a Baldwin (no
>I'm not picking on brands) 52" vertical, who never seemed pleased with the
>treble, said the magic words; "it hurts!"
>
>It's exactly the same phenomenon! At first listen, these hammers "sound"
>soft at the crown, but hard, very hard in the shoulders. The sound is a big
>muffled boom, but with little sustain.
>
>I went at C5 on the big upright with a single needle to probe the shoulder,
>certain I would fined hardener,.. but nothing. The shoulder felt is soft,
>much easeir to needle than a Renner, Yamaha, etc., even at the crown. I
>needled all over the place, and could not change the sensation of the tone
>one little bit!
>
>What is the problem?
>
>If you have experienced this, you will know exactly what I'm talking about,
>and I would sure love to hear from you. Yes, especially if you've been able
>to solve it.
>
>On my next visit, I'm taking a variety of hammers to test, but I'm not so
>sure hammers are the problem!?
>
>thanks, as always
>
>Mark Cramer,
>Brandon University
>