Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Even dip or even aftertouch?

With an even hammer line, or in the case of an upright, a hammer rest rail, I find myself choosing between consistent dip and consistent aftertouch. Perhaps due to inconsistencies in parts and in wear, I wonder if it's possible to have both. So, I'm interested in other techs' thoughts on which one takes preemminence.

I like both to be consistent whenever possible. However, you can have more give take in the key depth to allow for the proper after touch that we crave above. Allowing let's just say, 2 mm extra key dip just as an example, will give quite a change to after touch. Or, by raising the key height by 2mm, It will give more key depth automatically and thus more after-touch as well.

I start out by regulating two keys on each end of the keyboard and sometimes one in the center of the piano to EXACTLY what I want it to be before moving on with anything else. This includes first setting let off, adjusting the hammer line properly to the strings for whatever works best on that piano etc. There can also be some give and take on the hammer line too. Remember that factory specs are just that, "specs; guidelines" to what their recommendations are. That doesn't mean they will be exactly what the factory recommends and in fact in many cases, they are not. (I'm talking verticals at the moment) Once I am satisfied with the regulation on these preset keys, I then block these keys up on the front rail so they can't move after which I use an old fashioned key leveler that I received from the Everett Piano Factory during a tour eon's ago. I have 3 of these from 3 different tours.. A straight edge that covers all 88 keys. I level the keys first and then move on with the rest of the action regulation knowing that all of the rest of the keys will be where I want them to be or at least, within very close reason of one another. Any out of whack key dip can be regulated by adding more or fewer punchings to the front rail too if necessary.

Oops! Time to fly to my next appointment!!!

I came across this posting on the PTG website by André Oorebeek, author of The Voice of the Piano, the other day.

He says "There was a time in my professional life where I had a complete break through ... when I learned that a hammer travel distance gauge is not necessary anymore.... The final striking distance is the last procedure in regulation and it is ... defined by the amount of after touch."

This procedure will result in consistent dip and consistent aftertouch in uprights as well as the Yamaha grand pianos Mr Oorebeek mentions.

Ian

Greetings,
Aftertouch is paramount. Artists will forgive all sorts of variety in keydip if the aftertouch is even. For concert work, I set the keys to an even, consistent, dip, then after regulating the let-off with a given, straight, hammer line, I go back and first change the dip to give an even aftertouch. If a key requires more than .010" change from its pre-set position, I move the hammer a little to bring the aftertouch into compliance. By splitting the difference between the blow and dip to keep aftertouch the same, the differences in keydip disappear.
Regards,

Ed
Would you do the same on an upright piano?

Ian

>>If a key requires more than .010" change from its pre-set position, I move the hammer a little to bring the aftertouch into compliance.[/quote]

Ian asks:
>Would you do the same on an upright piano?

No, for two reasons. I love to work with pianos, yet this is how I pay my bills. The time involved in splitting these hairs has never been supported by upright players,it is expensive to spend hours on leveling, dipping, and aftertouching.
Secondly, the requirement for lost motion in an upright's action would seem to be a barrier, unless one decided to individually pad the hammershanks out to accomodate the variety. I have never heard of it being done, and I personally believe that taking an upright's regulation to that extent is sorta like making a great Hollandaise sauce for knockwurst.....
Regards,

How do you measure the aftertouch? Is it just by feel or do you look how far out the jack moves after left-off or some other method?

Both and everything.

Judging how the piano plays cannot be expressed only in measurements. This is why regulation is not a cookie recipe where you combine 46 mm of blow with 9.8 mm of dip with 1.5 mm of let-off etc and get a perfectly playing piano. Regulation is a bit of an art form which involves multi-sensory training and experience. Think of it as a holistic system, where regulation, small repairs such as pinning, voicing, and even tuning, all interact with each other.

This not so much the case, of course, when you are dealing with instruments that have limitations due to design, age or condition, such as old uprights with flattened hammer buts etc.

>>How do you measure the aftertouch? Is it just by feel or do you look how far out the jack moves after left-off or some other method?

When I have the let-off set where I want it, and the drop is at least at or below let-off, I set the aftertouch by placing a .035"-.045" spacer on the front punching, and pressing the key down until I see the felt compress. At this point, I should see the jack clear the knuckle just enough to let the hammer drop and feel the jack come free via the key. Escapement is an event, so for consistency, just pick a spot in the event as a benchmark, and set the punchings so that that place is arrived at with as even a press of the key as possible.
I think my sense of touch is beyond the average concert pianist's. I don't spend time on the literature, fingering,speed or expression, so I can focus on the elements of the machine. I spent my career pressing keys down and observing what happens, and by now, I am pretty dialed in on how hard to press the key to give a consistent aftertouch.
Even so, after it is all said and done, I will sometimes change things by a green or pink punching it feels like too much or too little when I am at the keyboard and playing it.

I agree. Imposing measurements on a piano is a bad idea. What do you do if they don't work out?

On the other hand making measurements on a piano can be very useful. For instance, I find it useful to know that my Schiedmayer will let off at 3 mm from the strings after 10.3 mm of key travel, and that ratio of hammer travel to key travel is about 4.0 just before the jack hits the butt.

Measurements are also useful as guidelines. André Oorebeck's post I mentioned above said the Yamaha Academy teach 0.4 mm aftertouch should be used to set hammer strike on their grand pianos.

Adding 0.4 mm to 10.3 mm told me my Schiedmayer upright might play well with 10.7 mm key dip. It does as it happens.

The hammer to key travel ratio tells me the piano should play with 10.95 mm key dip at 2 mm let off.

I am inclined to go with 10.7 mm but in your experience are there any good reasons to go to 10.95 mm and reduce the let off?

Ian

Five minutes before reading Ed's post, I had been looking at exactly what happens to the jacks on my Schiedmayer upright with 0.4 mm (0.016") and lesser degrees of after touch.

I placed a 0.4 mm spacer on the front felt; while looking at the hammer I depressed the key until I could just feel it on the punchings, then adjusted the let off button so the hammer was at its maximum travel and just at the point of falling back. I cannot claim to have Ed's eye or touch but I was trying to follow the general method he describes so well.

After removing the spacer, I depressed the key again to check the jack was on the point of escaping from under the butt, i.e. so that further pressure produced a slight gap between the jack and the leather. I also checked that this does not happen with less after touch (0.2 mm - 0.35 mm).

In other words, to measure the after touch required in an upright, add spacers until depressing the key slowly brings the hammer as close as it gets to the strings and to the point of falling back, then take spacers out until the jack is on the point of escape when you depress the key in the same way. The thickness of the spacers removed is the minimum after touch required for that key.

I would be most interested in your observations bearing in mind André Oorebeek's comments:

"Some pianists demand a smaller after touch or hardly any after touch at all. This is highly dangerous for soft play and it is only possible with a perfect action with maximum anti friction treatment. Some pianists demand a larger after touch, but that's stupid and literally a total waste. They usually don't know what they are talking about."

Ian

Andre said"
>>"Some pianists demand a smaller after touch or hardly any after touch at all. This is highly dangerous for soft play and it is only possible with a perfect action with maximum anti friction treatment. Some pianists demand a larger after touch, but that's stupid and literally a total waste. They usually don't know what they are talking about."<<

I agree. The more aftertouch, the slower the repetition, since the distance the key must travel upwards before the jack can reset increases. If we think of aftertouch as the distance between the jack's escapement and the end of the key's travel, reducing it simply means that the jack has a smaller window in which it must escape, and it's escapement happens closer to the end of key travel. That is why it becomes dangerous when this "window" shrinks, slight inconsistencies can cause some keys to malfunction as their jacks don't fully escape.
However, when using the aftertouch spacer to set keydip, the level of consistency allows minimum aftertouch with security, since the escapement of the jack is the actual event that is determining the setting, and key travel doesn't end for, say,another, .010 to .040" . If one is attempting to set .015" aftertouch by simply setting keydip to a certain spec with a certain blow distance, the tolerances in most actions will cause some notes to bottom out before they actually play.
In cases of minimum aftertouch, I am not so concerned with friction as I am with even let-off, drop, and spring tension. Jack position under the knuckle is important to the sense of touch under ppp playing. With little aftertouch, checking will perhaps be less in evidence under soft playing. With a very consistent let-off, and minimum aftertouch, many notes don't even fall back fast enough to go into check, but play quite well.
Regards,

It would be wrong to take André Orebeek's comments out of context by trying to apply them to any and all situations. First off, it is a grand piano action he is talking about, which can tolerate less after-touch when measured as key travel than an upright action. In his quote, he is referring to a $100,000 + concert grand, whose design and construction has been tweaked to the highest level. This is a new piano where one can reasonably expect near-perfect condition of hammers, knuckles etc.

Knowing André's work as well as I do, I can tell you for certain that he would sing a different song about upright regulation. And this especially true when dealing with an 80 year old candidate, with irregularly compressed butt felts, worn and flattened butts and everything else that inevitably wears from decades of use.

I think perhaps the final sentence of André Oorebeek's post referenced is the most telling one:
"Of course the after touch is mainly defined by the elasticity and hardness of the front punching but that is an other chapter..."

Jurgen

Yes, André Oorebeek was talked about a Yamaha concert grand but I thought he was making a general point when he wrote, "I learned that a hammer travel distance gauge is not necessary anymore." His point, as I understood it, was that after touch should determine hammer travel.

Ed Foote has explained the advantages of this approach in this thread, "Aftertouch is paramount. Artists will forgive all sorts of variety in keydip if the aftertouch is even." Though he also had concert grands in mind setting aftertouch can still be good for uprights.

James Carney said there is not much in Reblitz about aftertouch in uprights and there is limbo between 3/8" and 7/16" key dip. This may not sound much but it equates to 1/4" difference in hammer travel so it is highly significant in relation to let off. Alternative guidelines are needed.

In an upright the thickness of the punchings necessary to stop the keys at a chosen let off distance is the combined depth of the punchings needed to set key dip and the height of the spacer of required to set aftertouch. The question is what thickness of punchings to remove for aftertouch. André Oorebeek says this should be no more nor less than necessary. This implies the answer is to reduce the depth of punchings until one reaches the end of aftertouch as indicated by the point where the jack is ready to move off the butt leather when you start to press the key into the front punching. This is pretty much but not quite what Reblitz says on this matter:



Once key dip is set, one can set aftertouch with the spacer by adjusting let off buttons. This method allows for wear so the sample keys must be chosen with some care. In extreme cases increased key dip can compensate, as Ed Foote has pointed out.

The amount of aftertouch required in some uprights may be less than some may imagine. My recently arrived 89 year old Ibach project piano is certainly one of the candidates you mention; I did some measurements on it this morning after reading your post and, to my surprise, it seems to require only 0.2 mm aftertouch compared to 0.4 mm for my Schiedmayer.

Your final point about the cushion defining perception of aftertouch is interesting. Doesn't it make sense for this to begin at the instant escapement ends? Otherwise isn't one introducing an extra element of aftertouch that may confuse the pianist?

Ian

I am not sure that I have regulated an upright to these close tolerances. If you can and do, good for you. In that case why not split the difference and go with 10.775 mm?

Ian writes:
> Once key dip is set, one can set aftertouch with the spacer by adjusting let off buttons. This method allows for wear so the sample keys must be chosen with some care. In extreme cases increased key dip can compensate, as Ed Foote has pointed out. <<

Lest there be any misunderstanding, I don't change let-off to adjust aftertouch. I consider let-off the most important facet of the regulation, and any inconsistency in let-off is to be avoided. For most Steinways, I set the keydip to .390" first. Then after let-off is set, I will change the dip to achieve consistent aftertouch. If the dip has to move more than .010", I adjust the blow to compensate, but I do not change let-off!
Regards,

Ed, apologies. I was referring only to your point, which I had quoted, "Artists will forgive all sorts of variety in keydip if the aftertouch is even" and relating it to pianists in general. If the odd note in an upright does not escape fully a simple expedient is to increase its key dip a tad.

Setting let off with the spacer came from my interpretation of André Oorebeek's comments. In an upright with some wear there is a nice point as to whether one should set the let off distance or the aftertouch. Since a variety of things in such a piano are likely have more effect on how each note sounds than any variations in let off, it makes sense to me to set even aftertouch for the pianist.

Ian

In the "upright world" that I live in (pun unsupportable by facts...) I think if the dip is even, but the aftertouch is felt to be uneven, then there are mechanical problems or the aftertouch is just too darn small. If the mechanical problems are not deemed worthy of repair, increase the aftertouch even more to hide them.

And what kind of sound are you going to make after lifting the key only 1/10 of an inch, or whatever. (I wonder the same thing with a grand, but do not have that much experience.) Repetition aside, the key has to be lifted about halfway just to play another note with control. And with an upright (at least), the cream is when you can get things regulated so that the repetition works at about where the dampers release. Then the note can be repeated with or without damping in between. I am no player but look for this spot when playing and think it is important and overlooked.

I actually agree with all of the previous statements except the implication that no vertical piano is worthy of precise regulation. While many vertical piano owners may not be very sensitive, there are some who are and who will pay just as much to have their piano in prime condition as some grand owners. Andy (Cinnmanbear) is one example.

Although I usually don't get as precise with a spinet piano, I learned long ago from Jack Wyatt that a spinet or other vertical action can operate with the same or very nearly the same speed of repetition and dynamic range as a grand. In the end, it does come down to the amount of after touch each key is given.

A vertical piano does not have a repetition lever because it does not need one. It really doesn't need the hammer rest rail either if it is regulated precisely enough. Of course, the regulation would need constant maintenance if there were no rest rail and that would not be practical.

The key dip should be even as a starting point, yes but I agree with others that it can easily be manipulated with the addition or subtraction of a .010 paper punching here or there to facilitate an even after touch. The capstan adjustment is also just as forgiving as that of a grand. A quarter turn clockwise or counterclockwise here or there to facilitate after touch can be done.

If a vertical piano's checking distance and after touch are well regulated, the jack will return under the hammer butt with the slightest lift of the key. Therefore, it will repeat as fast as the pianist can operate the key and the rest rail is not involved.

In either case, grand or vertical, the capstan adjustment is the one that needs to be maintained the soonest and most often in order to maintain the precise amount of after touch that was initially set up during regulation. No amount of precision of after touch can be maintained unless the capstan adjustment is also adjusted back to the point where it was during the regulation. As soon as the hammer line in a grand starts sinking or lost motion in a vertical develops, all of that precision is lost.

It does not matter whether the piano as a six figure grand or a three figure vertical. If the goal is precise after touch, the capstan adjustment will need correction very frequently, such as at each tuning or even in between tunings. If it isn't, all of that precision in after touch will be lost after the piano is played for any extended period.

This discussion has been most helpful, and answered my question in another thread about finding the optimum key dip for my Schiedmayer upright. Thank you all.

Jeff, your point about repetition and damper release is very interesting and one I too would have overlooked.

Bill, I'd like to leave the last word on this topic with you. Your post told me exactly what I needed to know but didn't know to ask - not least about the return of the jack.

Ian