[pianotech] YC Capo Bars

[Roger Gable]

Will,
I'll use another word(s), "nasal" or "tight". I've noticed that laminated 
bridges create a sound associated with the facial expressions, such as when 
you squint or grimace or even the tightening of the jaw. Keep in mind, it 
can be difficult to express the character of sounds within our business as I 
believe our language lacks the identifiers associated with what we hear. Or 
maybe I'm just illiterate. That's the best I can do. Another associated tag 
that might point in the right direction is the sound we hear from low cost 
(cheap) imports in the 5 and 6 octave range  -- an obvious impedance 
mismatch either from hammer to string, or string to bridge. Remember the 
Kimball grands of the 70's and 80's, how "pinched" they sounded. Can anybody 
help (rescue) me here. My association of that similar sound comes from the 
cheap (low cost) laminated boards on consoles made by Story and Clark.
I can't address the sound of Ron Overs piano, as I haven't heard it, but 
there are degrees to all these sounds.
Roger Gable

----- Original Message ----- 
From: "William Truitt" <surfdog at metrocast.net>
To: <pianotech at ptg.org>
Sent: Sunday, September 19, 2010 3:40 PM
Subject: Re: [pianotech] YC Capo Bars


> Roger:
>
> How have you been able to isolate a "pinched" sound to laminated bridge
> caps?  What about laminated bridge caps would contribute to the pinching 
> of
> the sound?  Same question about laminated soundboards.  I remember hearing
> Ron Overs piano in Rochester, which I believe had a laminated board as 
> well
> as laminated caps.  Pinched is the just about the last word I would pick 
> to
> describe that glorious piano.
>
> Will Truitt
>
> -----Original Message-----
> From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On 
> Behalf
> Of Roger Gable
> Sent: Sunday, September 19, 2010 5:11 PM
> To: pianotech at ptg.org
> Subject: Re: [pianotech] YC Capo Bars
>
> Jon,
> I suggest an alternate repair. Reshape the original insert and have the
> machinist who is working with you check the hardness at the crown. It 
> should
>
> be around Rockwell 40. If not, explore having it hardened. It could end up
> costing less to harden the insert rather than machine a slot. Also, the
> water hardened drill rod you obtained from your local supplier is probably
> too hard and may cause buzzing at the duplex. Additionally, I've always 
> felt
>
> that the capo should have as few mechanical "interruptions" as possible. 
> Let
>
> me explain. It is known that when energy passes through different mediums,
> an energy reflection is created. This is experienced by the submarines 
> sonar
>
> when the sonar wave hits an area of different water temperature. It is, in
> effect, a different medium and a reflection is received back. The drill 
> rod
> is a different medium from that of the cast iron, as well as the 
> microscopic
>
> gaps that are sure to exist at the union of these two parts. An energy
> reflection from the vibrating string is certain to reflect back into the
> string. This reflection is going to be out of phase, creating an impedance
> imbalance that contributes to an ugly sound. This "pinched" sound can also
> be heard with laminated bridge caps or laminated soundboards.
> Roger Gable
>
> ----- Original Message ----- 
> From: "Jon Page" <jonpage at comcast.net>
> To: <pianotech at ptg.org>
> Sent: Sunday, September 19, 2010 9:53 AM
> Subject: Re: [pianotech] YC Capo Bars
>
>
>>A post last month showed the string impressions in the v-bar insert
>> on a 1996 Weber grand.
>> http://ptg.org/pipermail/pianotech.php/2010-August/027631.html
>>
>> I have a 1/8" rod to install into a machined slot. Photo attached.
>> The machinist will level an area and mill the slot with a 1/8" round bit.
>> Should the depth of the slot be .040" or more like .060"?
>> -- 
>>
>> Regards,
>>
>> Jon Page
>
>
>
>
>