after touch and key dip

[antares]

> From: David Andersen <bigda@gte.net>
> Reply-To: Pianotech <pianotech@ptg.org>
> Date: Mon, 21 Oct 2002 09:34:16 -0700
> To: "Pianotech" <pianotech@ptg.org>
> Subject: Re: key dip, dip in.....
> 
>> This means : a very sharp regulation with a dot on every i.
>> I (almost) always succeed in making a delicious and safe regulation with
>> enough after touch.
> 
>> We have done exactly that on the STW B in Bergen during the seminar and it
>> came out beautiful, so why not accept the approved (by almost all) standard
>> and use the 10 mm as the reliable basis it really is?
> 
> Fascinating.  Please share your exact method for making the 10mm key dip.
> Do you change key height
> as well as front rail punchings?

OK. Let us assume we would have to work on a Yamaha grand.

First we check the way it plays and the sound it gives. That will give an
initial impression.
Than we take out the Yamaha key frame tool (key frame bolt regulator and the
Yamaha key depth block (the brown one).
I check the key dip the way I have learned it at Yamaha by pressing down the
key with the pressure of about 250 grams (seams very normal and easy but
took me along time to master) and I move the key depth block from left to
right and back, to make sure that that, if the key is not strictly
horizontal, both sides have the same outcome/result.

We always have to change the key dip as the key bed moves along with the
humidity, due to the change of season.

So we measure the key height and it should be 64 (if it is not a CFIII-S).
If the key dip is like 9.5 mm and the key height is 63+ it is an easy
matter : we just raise the frame a little and make sure that afterwards the
frame is connected tight enough on all pressure points with the key bed at
the same time.
Most (Yamaha) techs are more or less a little tolerant about the key height
not being exactly 64 as it is also a matter of economy, that's
understandable.
If the key dip is 10 mm but the key height is 66 we have a problem.
In that case we can not put on the blindfold and just pretend that
everything is ok, so it means an extra hour of work by adjusting frame and
paper punching. 
As a last check I bang on the piano to make sure I hear no rattle coming
from a loose key frame.


>Why is a "sharp regulation" so crucial
> to proper key dip?   What is your method of finely refining the
> aftertouch, or "notch?"

First of all, sharps seem a forgotten chapter with many technicians. They
don't like to delve deep with their fingers or tweezers into/under the white
keys...it is always a nuisance because it is extra work..... If it
works...it works.
Of course every sharp is an active member of the family so if we feel
responsible enough we - must - do the job.
The height of the sharps should be 12 mm and we should check them with a
straight edge.
If we make an exact 10 mm white key dip than that is our basis for the
regulation.
That is why the preliminary activities of adjusting of key height and key
dip are so important : The pianist starts playing the instrument by putting
his hands/fingers down on the keys, and that is where it all starts.
The very first impression is the most important one : it causes trust, or
mis-trust.

When I did not know very much about grand regulation, I used to check the
striking distance with this yellow Yamaha measuring tool.
>From concert-Yamaha techs I learned how to go without this tool and play it
by 'feel' and it was a very important learning moment for me.
Actually it is amazingly simple and should be taught at all piano tech
schools :

We draw a curved line which represents the striking distance.
It ends just before the string as let off takes place.
Drop follows, and the up-going line goes down sharply for a very short
while.
At the end of this short line going down we draw a horizontal line : we have
reached the bottom, which is the front punching.
A perfect after-touch should be a movement of about 0.4 mm when we press the
key - gently - down into the punching.
Pianists often find this moment of after-touch the most important one and
three after-touch possibilities should be available to them :
'Hard landing, neutral/medium landing, soft landing'.

Hard landing means an after-touch of 0.1 mm - 0.2 mm
Neutral/medium landing is 0.4 mm
Soft landing is anything more than 0.4 mm but I would say no more than 1,5
mm.

A very small after-touch of 0.1 mm - 0.2 mm (hard landing) is the most
economical use of time and energy (which is what regulation is all about).
Very little movement is lost, the tone is loudest and hitting the front
punching feels very firm and maybe a little hard.

A neutral/medium landing is safer, as there is literally more generous space
available for the jack to move from under the knuckle.
I prefer this 0,4 mm. It gives a nice feel. The landing of the key is not
too hard and the regulation is trustworthy for a longer time.
The tone is generous, strong enough and does not need a lot of needling.
The 0,4 mm after-touch is standard.

The soft landing is actually a weird one and unnecessary.
It is a waste of time and energy as 'the work' has been done generously and
safely, so why more safety and more wasting time?
Because some (very few) pianists like this soft woolly feeling, that's why.

In the last stages of regulation we compare the feel of combined let off and
drop of the white keys with the sharps.
It is best to use a finger of both hands when depressing the sharp, in order
to feel the let off/drop (abnick) movement. Using both hands gives us a
double feeling and makes us double careful and sensitive.
The knicking movement of both whites and sharps should be EXACTLY the same.
This may seem all too easy but, as a matter of fact, it is an art in itself.
The more precise and sensitive we are, the finer the touch and the more
subtle and rich the tone.

The art and... sport in regulation lies in doing the whole process on sight
and feel, with only the key depth block as an absolute fact.

The greater art -and- sport in regulation lies in using the absolute minimum
of energy/economy in movement.
The whole process should be outlined in our mind beforehand and we must have
hearing image of the tone to come.
This last is most important during the process of voicing, but that is
another matter.
  
The most glorious moment comes afterwards, when we think we are finished.
When we have done well, we should have a striking distance of at least 46 mm
which is exactly what the striking distance tool shows.
If we become more and more professional or have a fine talent for
regulation, we often get more, or the most, out of it.

I remember doing a hammer change on a nice Bechstein B.
Bechstein grands are not the easiest ones when it comes to getting a
generous striking distance.
With this particular grand I reached 48-49 mm in the bass and 47 mm in the
treble.
It played man! and the tone was BIG!


> Thank you so much for your wisdom and experience.......David Andersen

Experience I have, but If I were allowed to make a wish...I would choose for
'wisdom'......

My pleasure.... and

friendly greetings to y'all

from

Antares,

Amsterdam, Holland

"where music is, no harm can be"

visit my website at :  http://www.concertpianoservice.nl/