High Partials

[Jim Coleman, Sr.]

Hi Jerry:

Usually when a damper is leaking the 6th partial, it is because the bottom
of the damper is touching the string hard at the 6th node and the top of
the damper is not touching its 7th or whatever node. Sometimes the bottom
of the damper is touching at the 5th partial node and therefore you get
the 5th partial ringing on.

The solution is to tilt the damper head to balance the pressure of the
top of the damper with the bottom of the damper. Make sure that the damper
head is properly aligned to the strings at both top and bottom and the
pressure is equal. If you have wedgie dampers there, make sure the string
spacing is right. If two of the three strings are spaced a little wider,
the wedge may not be making contact completely. The cure is to space the
strings first.

Of course in all of the above, we have been talking about vertical pianos.
In Grands, the same principle hold, but I'd have to change some of the 
words a little.

Jim Coleman, Sr.

On Fri, 10 Apr 1998, Jerry Lambuth wrote:

> Dear List,
> 
> I do a lot of work on old uprights, and have a recurring problem with new
> dampers
> leaking high partials - usually the 5 th or 6th - when the offending note
> or another 
> harmonically related note is struck.
> 
> Should I replace the damper (different size?, location?), try to needle out
> the offending partial?
> 
> Any input will be much appreciated.
> 
> Also anybody have a good solution to clean cat urine off the pinblock,
> agraffes, etc?
> I'm replacing the bass stgs. They're badly corroded ( blue green!)
> 
> Thanks.
> 
>  
>