I'm looking for explanations for why the use of the (sustain) pedal on an upright piano can produce repetition problems, particularly when playing softly and trying to use legato pedalling. I have a rough grasp of the components and dynamics in the action, but can't quite understand how and why the pedal lifting (and releasing) the dampers could interfere so much with basic repetition.

The piano is new and a tech is booked to come in two weeks to examine and rectify the matter under warranty, but I'd appreciate some kind of educational lesson regarding what is (or might be) going on.

With thanks in advance.

P.

PS Though I initially suspected my pedalling technique, I didn't have this problem on my previous piano, nor do I on another piano I use for practice when I'm away from home.

The dampers provide extra force on the wippen that pushes it back after playing. So you probably have some friction somewhere in the action which slows the return all the time, but is overcome by that extra force.

Further, without that extra weight on the whippen there is less weight driving/ pulling the hammer butt and you are experiencing hammer bounce between the wire and the back check.
Could be hammer let-off too. Regulation for sure and easily remedied.

At a guess I'd say this is most likely caused by tight centres.

Thanks BDB. I'm not sure I have understood you properly, but perhaps I haven't described the problem clearly enough.

The problem is most pronounced when releasing the sustain pedal (=adding the damper weight back onto the keys), yet rather than speeding the key return, it feels is as if the returning of the dampers is responsible for the 'jamming' of the key as it is being played.

Consequently, with lots of legato pedalling, it is not only that the note doesn't sound, but the key gets stuck, as if the jack didn't manage to return under the hammer butt. Some isolated keys did this for a while when I first got the piano, but the use of the pedal makes it much more likely to happen.

Or has my 'rough grasp' just let me down (again!) ... ?

Thanks Dan. I tried to describe the problem more accurately in the above response to BDB, which seems to suggest it is the returning weight of the dampers that is contributing to the problem rather than their absence. Any further thoughts?

Sometimes the damper spoons can be at the wrong angle and dig into the felt that they are supposed to ride smoothly on. This would cause what you are describing. Check their operation and polish them. Possibly replace damper stem felt if maladjustment has caused excessive wear.

The keys them selves may be front heavy and the weight of the wippen alone is not enought top push it down. Back lead may need to be installed. Easing the bushings will help. Also check the height of the balance rail hole, there could be some binding there.

It may be that the hammers are brushing against the dampers. The dampers may need to be lowered.

PNO40, I think it would be wise to give readers some context here. You could start by giving us the model, make and year and other history. That way people would not be looking at problems related to years of use and playing (wear of felts etc). In the end, I will be very surprised if this forum's answer to your question/problem will be anything but "have a technician look at it".

He said it was a new piano.

He also said this:

Every time I have seen this in a new piano, easing the keys resolved it.

'Easily resolved in person. 'Quite trick resolving it by word pictures over the "interweb".

Thanks for all the concrete suggestions, particularly those suggesting it might be hammers brushing the dampers, maladjusted spoons, and/or the need for key easing.

As I have still another week to wait before the tech arrives, however, I have a follow up question concerning the precise effect of the damper lift rod on the action dynamics. Here goes:

Let's say you are playing a chord softly in the left hand and gentling repeating it as part of playing the basic rhythm. The sustain pedal is depressed and hence the damper lift rod is keeping the damper levers detached from the action mechanism. The key repetition cycle will therefore have a set of dynamics in which the friction of the spoon on the damper lever and the weight of the dampers themselves play no part, and the various oscillations will have a distinct feel which you as a player can control in order to maintain the soft/pianissimo playing.

Then comes a chord change (again soft and repeating as part of the rhythm) and the time comes to release the sustain pedal, thus re-engaging the damper levers with the key mechanism before once more lifting them off.

My question: What effect does this have on the dynamic equilibrium already established?
Looking at illustrations of an upright piano action (the detailed illustration on page 47 of the Reblitz book, just in case it matters), I am trying to imagine how this re-engagement of the damper levers with the key mechanism affects the movement and balance of the wippens. If I have read the illustration correctly, then it seems to me that the returning weight of the dampers would have the effect of pusing the wippens down at the back, altering its overall balance, and consequently possibly altering (slowing) the motion of the jack, yet having no effect upon the motion of the hammer. Again, if I have grasped this properly, it seems that this would increase the likelihood of slowing the jack so that it does not return under the hammer butt on time, hence leaving the key 'jammed' and preventing repetition.

Does this make any sense? Or have I got it all wrong? In other words, is this (imagined) differential effect upon the jack's movement the kind of thing that releasing the sustain pedal can have on the action? And if so, does that mean that the regulation of the sustain pedal is critical to overall action regulation, rather than it's being a simple user preference as is sometimes suggested?

Finally, if this is the kind of effect the returning weight of the dampers can have, is it also the case that the more 'lax' the sustain pedal is set (i.e. the more lost motion in the pedal before damper lift begins), the greater will be the force of the returning dampers when the pedal is released, or is that force constant across the different adjustments of the pedal from 'lax' to 'tight'?

Again, I'd welcome any feedback of those who know these things inside out so that I can see if I am at least beginning to get some grasp on this.

With thanks in advance,

P.

When the pedal is down, the touch at the end of a keystroke is lighter. This makes people more likely to play louder when they use the pedal, which is not a good thing. It also makes lazy people use the pedal more. There may be more subtle effects, but those are the big ones.

Thanks BDB. It's the subtle effects--on the dynamics of the mechanism, rather than the resulting sound--that I'm enquiring about. Any thoughts on that?

I appreciate the fact that you responded to my post, BDB, particularly given that nobody else has, so please don't take the following in the wrong spirit. However, if you look at my post, I think you can see that I have a very specific (and dare I say 'technical'?!?) question that I took some time to formulate carefully. It is not about the generic function of the sustain pedal (as if this was a question to post on the Technician's forum rather than an opening question in Piano101) nor was the question about the purported proclivities of piano players categorised according to ranking on a work ethic scale.

So, might you, or any of your colleagues, venture an answer to the particular question asked? It seems to me to be clearly on the technical end of the spectrum and hence appropriate to this forum, but I'm tempted to see if the ham-ams over on the Piano Forum might be more responsive ...

Actually, for what you are paying me, not only am I not willing to address your specific question, I am not willing to look at your question carefully enough to figure out what you want to know.

Ah, yes ... the spirit that built PW! Long may it last!!

as I see it if the pedal is released franckly, it can disturb a bit the touch before you push on it again.

but it should not be a problem, dampers help the retun of the parts so they work better on a new and possibly tight keys and action centers.

your question is not very well expressed, but all techs think of key easing when this is asked (repetition in regard of pedal use)

there is no much dynamic effect on a vertical you can feel a little shank or key flex but the weight of the hammer is about zero hence reduced dynamics perception.

Thanks Isaac. Much appreciated.

P.