damper problem (probably just stupidity on my part)

[Richard Brekne]

Assuming you have good quality and condition damperfelt then basically, you
have just a few basic issues that contribute to good damper function.

1. -- Regulation, which you say (at least with regard to timing) is correct.
2. -- Damper pressure on the strings. Spring strength in most uprights.
3. -- Damper size, and position on the strings.
4. -- The mass of the dampers and head.

no doubt more things could be listed up here.. but these are amoung the
primary concerns.

As far as I can see, you've insured the basic timing is correct, but the
other three points you have not commented on. So I would check these out.
Try increasing spring tension a bit on a few notes. Also ascertain whether
or not your new dampers are sitting on relavant string nodes. You may also
try adding a bit of mass to the damper heads to see if any change is made as
a result of that.

Another suggestion is to see if the damper leak is primarilly related to
bass strings or indeed even over the entire piano. Mute off the entire bass
with a towel or your arm or some such contrivance and play the middle
section to see if these notes then damp significanltly better.

Otherwise, suggestions as to reading articles in the journal are a good idea
to follow up. Not mentioned so far is Del Fandrichs articles on the subject.
Well worth a read.

Cheers
RicB


David Ilvedson wrote:
> More than likely the problem is length of bass dampers.   The first 
> thing is checking if your arm against the bass strings eliminates the 
> overring when playing the tenor.   Read Bill Spurlock's articles in the 
> Journal on making dampers...
> 
> David I.
> 
>  
> 
>  
> 
> ----- Original message ---------------------------------------->
> From: <Tvak@aol.com <mailto:Tvak@aol.com>>
> To: <pianotech@ptg.org <mailto:pianotech@ptg.org>>
> Received: Tue, 30 Nov 2004 22:33:26 EST
> Subject: damper problem (probably just stupidity on my part)
> 
> 
> List
> 
> I don't think anyone can help me with this, but here goes...
> 
> I replaced the damper felts on an Acrosonic spinet.  My initial 
> diagnosis and decision to replace the damper felts was based on the 
> familiar sound of ringing after notes were played.  I did notice that 
> the spoons were lifting most of the dampers very early, preventing some 
> of the dampers from having good contact pressure with the string, but I 
> found a few that were OK and when I checked them, they didn't dampen 
> very well, either, so I decided that the felt (which was original to 
> this 1940s piano) needed replacing.  It was my hope that the additional 
> height from the new felt would remedy the spoon lift timing, but if not 
> I was ready to regulate those suckers, too.
> 
> When I put the action back in the piano I found that the dampening is 
> not much better.  But why?
>      1. There is follow through on all the dampers.  (In case I'm not 
> clear, I mean that the damper will
>           move with the string when the string is pressed toward the 
> soundboard, indicating that there    
>           is proper pressure for the damper to dampen the string.)
>      2. The spoons are indeed lifting at the proper time, and so they 
> are not impeding the damper levers from pressing                against 
> the strings.   (There is follow through.)
>      3. The damper pedal is not holding the dampers away from the 
> strings.  (Again, there is follow
>           through.)
>      4. The dampers are seated well on the strings.  It's not a string 
> level issue.  (It's not one of the
>           three strings on a trichord, for instance.  It's all of them 
> equally.)
>      5. The dampers are aligned to the strings properly.  The bichords 
> dampen both strings equally, the trichords dampen all           three 
> equally.  Just not enough, it seems.
> 
> They do all dampen somewhat.  I mean, it's not like the pedal is down.  
> But there is definitely sound after the keys are returned to the up 
> position.  It sounds just about the same as it did before I replaced 
> them!  (A second question might be, who among you would charge this 
> woman for your work?  I won't, until I can get it to sound better.)
> 
> I did file the hammers, which were heavily groovy, man.  I didn't change 
> the hammer blow distance though, due to the spoons initially being on 
> the early side, I thought it was best to just leave it as is.  I was 
> happy that the spoon lift was OK with the new damper felts.  I hate 
> regulating spoons.  I didn't do anything else to the piano, other than 
> replace a few bridle straps.
>     
> I'm going back on Saturday to check it out, and see if perhaps the felt 
> has started to conform to the contour of the strings and dampen better, 
> but if they don't, then what?  I'll try dampening all the treble strings 
> that have no dampers with a towel and see if the ringing goes away, but 
> I don't think it will.
> 
> Any ideas?  Is there something I've not thought of?  Any diagnostic 
> procedures that might shed light on this?
> 
> Thanks in advance,
> 
> Tom Sivak
> Chicago PTG Associate
>