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The local techician's guild meeting here recenting discussed the alleged 'flexibility'
of keybed as a 'shock absorber' built in exclusively in Steinway and/or grands.

Personally I have never heard of such nonsense nor would it make any sense.

Others,please.......

Norbert Marten
www.heritagepianos.com

Hi Norbert- well, not having been there, I would have to agree with you. I know I dont want to feel any "flex" when I'm playing hard, and the purpose of properly bedding the keyframe is to avoid a mushy feel to the keys. Bedding so that the frame mates perfectly with the keybed is one of the first things one does when regulating. Or am I not understanding the question?....Sam

One member of the local guild became somewhat perplexed that this issue shouldn't be immediately debunked for what it is!

There seems to be a 'small war' going on over this nonsense here and what bewilders me is that purportedly serious technicians seem to be taking feverishly part in it.

P.S. Hopefully the 'Orientals' don't get a hold of this 'secret' in their quest to improve their own pianos of today!
[That would be another act of 'blasphemy'! ]

[ December 05, 2001: Message edited by: Norbert ]

Hi Folks,

I have lurked on this list for close on a year, so perhaps it is time to contribute something.

I suspect the "shock absorber" being referred to is in fact a reference to the fact that Steinway has a slight crown in its keybed. It curves ever so slightly up towards the center of the keyboard and down towards the bass and treble.In the region of 1/32".
This curve can be seen just looking at the keys. (although it is very slight). Any shock absorbtion would most likely take away from the touch of the piano. A more likely reason would be for visual appeal, or perhaps egonomics in that a persons hand tends to lower as it is moved further from the person. Of cause there is always the marketing angle, ergonomic design ,shock absorbsion. I suspect the true reason leans towards visuals and marketing, since Steinways have had this feature a lot longer than people have being aware of ergonomics

Take Care
Brian

The "curve" visible when looking at the keys is the way that the keys are levelled, not a curve in the keyframe. Steinway and others recommend when levelling keys, to make the center 1/32" higher than both of the ends. The keybed is not curved, the key level on the keyframe is. I have heard several reasons for this, but never one from the horse's mouth, so I won't speculate on that here.

Sam is correct that this is the way that the key height is set and has nothing to do with the keybed. The rationale that I've always heard for crowning the keyboard by about 1/32" in the center is this. Most pianos get played more in the center of the keyboard than at the extremes. The balance rail punchings that regulate the key height become ever so slightly compressed from playing over the years causing a slight reduction in key height and the compression will of course be greater where the playing is greater. By this small crowning of the keyboard at the center the gradual small change in key height will therefore in the typical case of a piano played more in the center tend toward a level rather than a concave keyboard as the piano ages.

It's interesting the hold "Steinway" has on the imagination of people not having a craftsman's knowledge of pianos that normal characteristics of the typical piano such as this become special features propretary to Steinway.

The flexible keybed theory sounds pretty lame to me. I would expect that the amount of pressure necessary to flex the keybed of a Steinway or just about any reasonably well built piano would far exceed what any pianist can bring to bear either by playing or standing on it. Perhaps a test of the theory at the next technicians guild meeting is in order. Let me offer a modest proposal. Bring a Steinway and a long ladder to the meeting and remove the keyboard. Have the heaviest technician present stand on the center of the keybed. Using the ladder have the next heaviest climb on his shoulders. Repeat until the keybed flexes or until all technicians present are used, and from the combined weight of the technicians and the area of the bottom technician's feet calculate the pressure required to flex the keybed. That should settle it.

Niles Duncan
Piano rebuilder, Pasadena, CA

[ December 08, 2001: Message edited by: Niles Duncan ]

I didn't know the Canadian technicians could take their Guild exams at Sears!!

Keybeds must be flat. No one has ever made a curved keybed (on purpose at least). If the keybed had any crown in it, the keyframe would slap like mad when you played the piano. The wooden "knock" sound you'd hear with every push of a key would sound like someone banging on your front door with a hammer.

The old Kranich & Bach grands had what they called "floating keyframes"....could they have meant this? The idea was to make the keyframe flexible so that it would bend enough to conform to the keybed. Sounds like a good idea, the problem was that was just one of the many areas where they reinvented the wheel in that action, any one of which was sufficient to let them lay claim to having designed the worst grand action in history. Even with this action though, the keybed was flat.

I gues next month the topic will be "Moving the strings to the bottom side of the soundboard".............

Larry and Niles- who said piano people don't have a sense of humor? You two made my morning with your responses....clever stuff. Thanks for the lift........Sam

Larry wrote:


Way back in the dawn of time the first piano I ever rebuilt was a Kranich & Bach. It definitely had the worst action I've ever come across, and afterwards I swore that never again would I touch a Kranich & Bach. One of the difficulties in working with the action was that regulation performed on the bench would change when it was put back into the piano because of flexibility in the keyframe. At the time I thought it was a defect in the design. Now I see that it was a designed in feature.

Niles Duncan
Piano rebuilder, Pasadena, CA

As a newbie to post in this forum I will risk pointing out that the keybed is in fact crowned. To quote from www.steinway.com

Keybed : - " Front center is crowned contrasting the reverse-crowned action frame for snug fit. This design intensifies key movement and prevents "slapping" during heavy playing. Large maple dowel ends provide a solid mount for adjustable brass touch-regulating screws. Thickness: 1-3/4" (4.45 cm)"

The spec I refer too applies for the S M L B and D. The marketing ploy here is to intensify key movement.

regards
Brian
(hoping I am not flashing vast amounts of ignorance)

Thank you all!

It shows the sad state of the affairs of some of our local technicians here who try to gain 'status' among their impressionable unworldly peers by talking sheer nonsense.

Perhaps - they DO take their exams at Sears!

[Problem is that - I don't need a new tie!]

Norbert Marten
www.heritagepianos.com

You're not flashing any ignorance, Brian. You're simply a victim of the marketing department at Steinway. They're not the only ones who make mountains out of molehills, but they are in the lead for the most examples of it. Let me translate the marketing hype:

Production foreman: "We need a thick, solid keybed that won't warp, and that will stay flat."
Accounting department: "Nope. Too expensive. Figure out another way."
Production foreman: "Well, we could make one out of slats, but it's hard to make them flat. I guess we could just sand a little more toward the edges to make sure it isn't concave."
Marketing department: "Go with the slats. We'll tell people how those old cheap solid keybeds trap moisture, and our revolutionary slat keybed allows air to circulate. Then we'll tell them how we specially curve the keybed to eliminate other problems."

(Notice to all lawyers: I wasn't at this meeting, so all comments are intended as humorous fiction)......

Consider this - if the keybed had any crown to amount to anything, the unacorda pedal would play heck making the action slide. Many pianos have hardwood inserts in the keybed for the adjustable glide bolts to slide on. And when we say "a keybed should be flat", understand that there is flat, and then there is f.l.a.t. There is going to be some unevenness the best you can do, which is why the glidebolts are there in the first place.

So basically, Steinway's comment is simply taking a tiny, minor detail and adding a heap of marketing hype and straining it through semantics so that it reads like a major technical achievement. This is probably what is creating the discussion among the technicians who were in Norbert's store.

But then again...has anyone noticed Steinway's actions getting lower to the floor on the treble end when you push the unacorda pedal?

Hi larry.

In both my postings I made reference to the fact it is a marketing ploy. I do not really believe that there is anyhing more to this "feature". IMHO Steinway have little that sets them apart from other good instrument makers except perhaps for good marketing. Personally I prefer a Bechstein. (not that I own a Bechstein or a Steinway)

BTW, I am a long time visitor to www.pianosinc.net. Having being suckered by a piano purchase before, I have an extra appreciation for your site.


Brian

Reminds me of the Sales rep that tried to tell a bunch of us techs that the nose bolt on the plate served to transmit vibrations, and thus amplified the tone. Hee Hee

The sad thing is that is not coming from a
'sales rep' but from supposedly certified guild technicians in our area.

Taking basic piano lessons and understanding
what PLAYING a piano is all about.....
....sometimes can help.

P.S. Some of these guys are watching this board. Where is their appreciated input?

Norbert Marten
www.heritagepianos.com