repetition/backcheck problem

Kent Swafford kswafford@earthlink.net
Mon Aug 24 21:25 MDT 1998


DMCKECH wrote:

>Well, here is the real kick in all this. I did a walkabout in the building 
>and tried a number of different brands and found that I could make this 
>happen on all! I must be getting good at it.  :-)  Some of the actions 
>have had parts replaced and some are original. 

Just to review, "this" is:
>>One of the problems was during a short but fast 
>>repetition, on one note, the backcheck would catch the tail of the hammer 
>>thus failing the repetition. (Two to four or five strikes and fast enough 
>>repetition that the key does not come all the way up.) 

I believe that the fact that any piano can be made to do this is mostly 
irrelevant. Some actions _are_ much worse about this than others. To make 
sure we are talking about the same thing, on repeated blows where the key 
is not allowed to return all the way to the at rest position, the back 
check works its way "down" until the hammer is close to the at rest 
position, but is in check, and only releasing the key to the at rest 
position will undo the jam.

I had have seen this problem on several Steinways. I once had 2 D's side 
by side, one had the problem, one did not. I swapped wippens and 
hammers/shanks from the same note on each piano and it made no 
difference. The repetition problem did not move with the action parts but 
stayed with the piano.

My best guess (and this is still a guess) is that this problem is the 
result of a combination of factors. The above-mentioned D got much better 
repetition after the hammers were replaced (with a set that was as close 
to a duplicate of the worn-out set as you will ever see), but the keys 
were weighed off carefully to better match the hammers.

I for one would check the key-weighting as a contributing factor. Another 
thing I would check would be all the factors that go into allowing very 
high checking -- tail shape, back check height and angles, etc. Make sure 
you can get high checking.

>This begs the question about proper technique in playing. Not being a very 
>good pianist, I need to consult about this. For a fast and short single 
>note repetition, I was taught to use fingers one through four in quick 
>succession not one finger repeating rapidly. With my limited ability, I was 
>able to get good repetition on the pianos I tested by using the 
>multi-finger technique. When you get a chance, please try this out. 
>Obviously, I would feel better if someone discovered this as well!

Just because the repetition is possible at one rate with one amount of 
partial key release, it does not necessarily follow that overall 
repetition is good. Are the keys so compliant, for example, that their 
flexing does not allow repetition at some particular speed? Check for 
floppy keys.
 
>I will tactfully broach this subject with my customer. As stated in my 
>post, he is a very good pianist and I am sure he knows how to repeat a note 
>in different ways. Perhaps it was our luck that one piece he was working on 
>called for this type of one finger repetition. It must be stated that he is 
>very satisfied with the action in all other aspects. Trills, touch and tone 
>are no problem.

Be careful, sir. My own feeling is that the problem(s) may yet be found 
in the piano and not in the pianist.

>Don McKechnie
>Ithaca College
>dmckech@ithaca.edu


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