double strikeing notes

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Jack
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Post by Jack »

Barrie Heaton wrote:Sound like the tapes are too tight or one of the slap rails are too close - if you play softly do the hammers double strike a note
Barrie,
Barrie Heaton wrote:Sound like the tapes are too tight or one of the slap rails are too close - if you play softly do the hammers double strike a note

Barrie,
Hi Barry,

I came across this thread whilst looking for information on 'repeated notes' and noticed your question above to the original poster, i.e.: "if you play softly do the hammers double strike a note"

I have precisely this problem: if I play softly the hammers strike a double note and you can feel the 'double hit' as the keys are depressed, almost like a two-stage strike.

This only happens when playing softly, and from the D below middle C, all the way up to E above middle C, though it's much worse at the lower end of this range.

This is a new piano so I'm a bit disappointed, and the obvious question is what is the cause of such a phenomena and can it be easily cured? Or should I consider sending the piano back?

Thanks for any thoughts.
Barrie Heaton
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Post by Barrie Heaton »

There are many factors that cause this problem the main ones on uprights are lost motion, incorrect depth of touch (which is what happens when you have lost motion) Jack slap rail to close, Damper slap rail to close - all can be easy fixed but if the piano had been set up in the first place should have not happened

There is one more which is to do with key hammer ratio but you normally only get that when new hammers have been put on that are too heavy.

On grand’s lost motion, incorrect depth of touch, rep spring set to strong and Key hammer ratio.


Call the shop back and get them to fix it

Barrie,
Barrie Heaton
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Jack
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Post by Jack »

Barrie Heaton wrote:There are many factors that cause this problem the main ones on uprights are lost motion, incorrect depth of touch (which is what happens when you have lost motion) Jack slap rail to close, Damper slap rail to close - all can be easy fixed but if the piano had been set up in the first place should have not happened

Call the shop back and get them to fix it

Barrie,
Thanks, Barrie. I'm calling them back to have a look.
But just so I sound a little knowledgeable (I'm still learning about the techical side of things), could you explain exactly what 'lost motion' and 'depth of touch' are?
Thanks very much.
Barrie Heaton
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Post by Barrie Heaton »

Depth of touch (dip in the USA) is the distance the key goes down from rest to play, on most uprights it’s about 9.5mm to 10mm

Lost motion this is when you play the key and there is a gap between the capstan at the back of the key and the heel of the whippen. This normally happens with wear or compression of felts.

What should happen is as soon as you touch the key the whippen should move in unison with the key. So if you have 1mm of lost motion at the front of the key you will only have 9mm instead of 10mm on a 10mm Depth of touch piano.

Barrie,
Barrie Heaton
Web Master UK Piano Page
Jack
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Joined: 05 Mar 2007, 00:35

Post by Jack »

Barrie Heaton wrote:Depth of touch (dip in the USA) is the distance the key goes down from rest to play, on most uprights it?s about 9.5mm to 10mm

Lost motion this is when you play the key and there is a gap between the capstan at the back of the key and the heel of the whippen. This normally happens with wear or compression of felts.

What should happen is as soon as you touch the key the whippen should move in unison with the key. So if you have 1mm of lost motion at the front of the key you will only have 9mm instead of 10mm on a 10mm Depth of touch piano.

Barrie,
Thanks Barrie, I understand. I am learning slowly!
Jack
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