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On another forum it was mentioned that speed of key lift affected playing and too fast could cause abrupt damping and choppy sound.

I don't know enough about how a damper works mechanically. This question is new to me but I've been through a bunch of flame wars over how key press supposedly affects tone, so I'm a bit skeptical.

Doesn't a damper trip and fall at some gravity determined rate? or is it coupled to key position, and fully controlled?

The dampers in any piano are controlled in two or three ways. Depends on the pedal functions...whether you have a sostenuto, bass lifter, or muffler rail for the center pedal.

The basics--

1. Key travel; On grand or upright the damper is lifted from the string by how far the key has traveled. Usually at about 1/2-stroke the damper starts to lift from the string.

Grands; Damper underlever is weighted and lifted by the key-end felt...like a seesaw lifting a weight at one end. Most grands want the key to travel 1/2-way before the damper underlever is engaged by the key-end.

Upright; Damper is pushed by a strong spring to keep it in contact with the string (to do it's job!) and lifted by a spoon sticking out of the whippen and pushing on the damper-lever. As the key goes down, the spoon rotates out and contacts the damper lever at about 1/2-stroke, and then the damper leaves the string.

Both grands and uprights also control the damper return with the key. In other words; the damper won't get back to the string until you release or raise the key high enough to get the damper back on the string. They don't 'trip and fall'.

2. Pedal; Both upright and grand can also lift the dampers off the strings with the damper pedal. All dampers, all at once. You might release the pedal very quickly and get a 'bang!' from a grand or upright as they all move at maximum speed...but that would be very poor technique. No trip, no fall..just your foot and technique.

3. The Trip and Fall does exist!
The sostenuto pedal, which can be found on both uprights and grands, can hold selected notes open for you (...the pianist's third-hand) and when it is released there is more of a 'drop' as the damper-tab slides off the blade holding the note, but that would be the only 'trip and fall' on releasing a damper in normal play. Only the sostenuto could be called 'trip and fall' for damper release. Not the keys, ok?

You can search a couple sites easily enough to see how the piano's action works. Lots of moving parts in there!

Hope that helps,
I am,

Thanks.

I've looked at a couple of those before but didn't really get it until this time. Lots of parts.

I see the key only partly controls the damper. It is not linked, but just presses. So if the key lifts very slowly, the damper stays in contact with the mechanism until about string contact at half way, but if the key lifts very quickly, the damper returns at its natural speed moved by either gravity or spring force. If the key can actually lift that fast. You can't actually lift a key, they don't have loops for your finger; all you can do is release it and let it fly up. They must come up like a seesaw, by the weight of the parts past the pivot.

When viewing the mechanics of the action, keep in mind that every part is moving in an arc relative to a center point. The typical underlever has two center points of circular mechanics. How these two arcs relate mechanically to the arc of the key end; plus the flex of the parts, especially the key and damper wire, at different speeds; plus the friction at the center points and contact points, again at different speeds; all combine to work within a variable that hopefully an experienced pianist can adjust to while playing.

Only one thing related to "key press" affects tone...the speed at which that hammer is moving just before it hits the strings....everything else claimed, is purely bunk.

If anyone disagrees with you on this, send them to this article... "The Piano Voodoo of Tone Production"

http://blog.twedt.com/archives/222

But Emmery, are your playing piano, in the end ? is not it a percussive instrument ? or not ?

One basic things that pianists are doing to modify tone is allow more or less key thump noise with a more or less dampened key (finger touch the key or no) , with more or less synchronization between the key thump and the tone attack.

And more or less early opening of the resonant structure with the use of sustain pedal)

I will certainly not pretend that moving/vibrating the key after tone production is doing anything to tone, for instance, but just before the key bottoms there are yet a good range of possibles that influences the tone, hopefully.

not on the modern cheap grand where those possibilities are limited

That is how I understand it anyway.


Should be interesting to record only the thump noises produced by a pianist on a concert grand, without any tone if it was possible.

What I was told that on actions where the hammers are at 90° on the shank, and where the shank is strictly parallel to the keybed when the hammer hit the strings, (most classical setup here have some "overblow", shank rise above the horizontal a little) playing strong can make the hammer block on the string.
The letoff regulation also is to be done at 2 mm and not more near the strings (as it can be done when the hammer is a little open on the shank and (possibly) the shank flex allow then for a strong FFF without blocking.

The sensation when playing too strong is that of an "electrical shock" under the finger.

I see the role of the shank flex there, a security, some damping of unwanted noises...

°

I have always agreed with this but know I'm in a minority. I'm also a heretic who does not think different brass alloys make a trombone sound different.

But I had not run into this idea of speed of key lift until this last week.

After looking at the animations of key actions, I remain very skeptical there is anything to it. I don't see how you can lift the key fast enough to lose contact with the damper lifter offer thingie, so I don't see any way to get the claimed effect.

By the way, is it REALLY necessary to make the action so complicated? Couldn't we redesign it with about half the parts?