Friday, 22 January 2016

GRAND REGULATION – part VIII



In part VII of the series on grand regulation we discussed the two methods of regulation for grands, the Dip and Blow Priority. Now that we know the differences between these two methods, two decisions must be made before Section IV ‘The Touch’ can be begun. The first decision is what procedure to use to accomplish the regulation process. The other decision, depending upon which Priority method was chosen, is to determine the correct measurement for the dip or blow. Once these two decisions have been made, the remainder is a piece of cake. Without these two decisions, regulation becomes a long, hard task with lots of wasted time.

Let us look at some of the many grand regulation procedures that are available to choose from. This list is by no means all inclusive, and just because a certain procedure has been omitted from this list does not infer anything about its relative merits and value to us.

The five procedures listed on the left are Dip Priority, the five on the right are Blow Priority. In viewing this chart you will notice that some procedures have more steps than others. But pay more attention to the order in which these steps are listed. For instance, in procedure no10 the whippens are aligned to the knuckles as step number three. But in step number seven the hammers are aligned to the strings, making realignment of the whippens necessary. Other procedures listed have similar mistakes. I would certainly modify the order of some of these procedures to eliminate such needless doubling back.

If you were to regulate an action, which of these procedures would you choose? Should you select the one that is from the factory manual for the brand of piano being worked upon? If so, then each time you regulated a different brand of piano you would use a different procedure! Needless to say, this is awkward. Or should you select a procedure written by your favourite author to use on all brands of pianos? Chances are that your author’s procedure is different from what the manufacturer calls for, and may not be as detailed as the factory manual. As an example, some pianos have an auxiliary whippen spring. If you did not know this, and the procedure you were using doesn’t mention it, you would probably overlook it. Well then, should you select the procedure that is the most detailed? I don’t believe so. Just because it has 125 steps doesn’t mean that it is better than one with 50 steps!

How do you decide upon a procedure? Obviously, you want the one which is easiest and fastest for you. People differ in their abilities and knowledge. What works best for one technician may be awkward for another. I suggest that everyone make up their own procedure to suit their own needs. In creating your own, remember that the order of steps must be logical so that the minimum of doubling back occurs.

As a help here, consult the Grand Regulation Chart which appeared in the 2nd post of this series on grand regulation. Naturally, you will want to include those steps such as reshaping hammers and rebushing keys that are normally done when regulating an action. Every step should be in a convenient order to go along with how you regulate. Do you bench regulate or do you regulate at the piano, or a little of each? In that case, you have to create your own procedure.

Now that the procedure has been decided upon, next is to decide what measurement to use for the dip or blow. Let us take the example of a Blow Priority method first. In various piano technicians’ manuals you can find many different measurements for blow for a grand piano. Be aware that some of these measurements listed in the piano technicians’ manuals are different from what the manufacturers state in their manuals. Also, be aware that when the pianos are made, the factory may or may not use these specific measurements. One reason why is the varying thicknesses of grand piano plate castings.

Remember that these specifications are for brand new pianos. As an action becomes worn, compromises must be made. It is not feasible to replace a perfectly good set of hammers just because they are starting to get worn! So how does one decide what blow distance to use? All that I can say is to try sample keys, maybe one in each section of the action, and adjust the blow within tolerances to create the correct aftertouch (assuming that the other steps are properly regulated on these sample keys). If the blow distance must be altered beyond tolerances, then maybe the action needs to be repaired or rebuilt before it can be regulated.

Taking now the example of the Dip Priority method, your task is no easier. Many technicians say that the dip should be 3/8”. This measurement is supposed to be valid for all grands. But is it? I have had technicians argue that the key dip should never be altered. Well, believe me, if the dip on a Concert grand is set at 3/8” and the artist complains that the dip is shallow for him, you had better change it! This can often be the case with foreign artists, because they are used to a slightly deeper key dip. A technician who insists upon a 3/8” dip would also run into big problems, if he worked for instance for a Kawai dealer. The Kawai factory manual specifies 10mm (.394”, 3/8 = .375) for their verticals, 10.5mm (.414”) for their 7’4” and smaller grands, and a whopping 11mm (.4334”) for their concert grand!

Just as in selecting the proper blow distance, to select the correct key dip, first start with the measurement specified by the manufacturer. However, if this measurement when tried on sample keys does not conform to either standards or to the liking of the pianist, then by all means, change it. I would far prefer to adjust the blow or dip on a piano to make an artist happy than to alter it in a way that is permanent, such as in voicing. Either the dip or the blow can both be reset easily later, because they both should be changed equally across the keyboard from what they previously were. Simply reverse the procedure used to alter the action, and everything will return back to what it was.

In conclusion, I would like to state some limits within which it would be acceptable to alter the dip and blow. I would never alter the dip much over .025” beyond what the manual specifies for that piano. Likewise, I would never alter the blow over about 1/8” to 3/16” from the factory specifications. Rather than go beyond these limits, I would prefer to replace the hammers, reround the knuckles or replace them, or to repair or replace the whippen cushion felts.

  

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