Theory and Practice

[John Delacour]

At 6:20 PM +0100 12/21/01, Richard Brekne wrote:

>JD, I thought your last post on this subject matter was most 
>interesting, and I
>look forward to some truly relevant critic from the other camp.
>
>One thing though.... I am not really sure just how important this 
>all is for the
>actual process of building an instrument. What kind of design issues could be
>affected by considering this matter one way or the other ?


I've change the topic line to answer this because, curiously enough, 
I was asked the same question today when I mentioned this discussion 
to David Winston (the man who rebuilt Beethoven and Chopin's pianos). 
He'd ordered some strings and we were discussing details so I took 
the opportunity of surprising him with the bridge question.  I was 
only a little surprised that he'd never given it a thought, since 
many fine makers and restorers have produced fine-sounding pianos 
without and theoretical understanding of acoustics at all.  Once he'd 
said that my view of things seemed to be the right one, he asked what 
did it matter?

I sometimes think of a little work I read long ago by Mao Zedong 
called "Where do right ideas come from?" which I found very affecting 
at the time but which I don't have any more.  Experience comes first. 
Theory separated from practice is perfectly useless.  As we gain 
experience through repeating actions again and again, we gain 
intuition.  To me the craftsman is every bit as much an artist as the 
concert pianist or the Dutch painter.  The craft enters the blood and 
a knowledge comes from practice that we are hardly aware of; we know 
things that we do not know we know.  Many of the finest craftsmen 
have been uneducated or even illiterate but have had that quality of 
intuition or genius that is necessary for the great craftsman, and it 
a quality that must be consciously developed through informed trial 
and error.

Then there is theory.  We are puzzled by questions to which we have 
the solutions but not the reasons.  Why, for example, does that 
replacement string need to be tuned every day for a week?  It's not 
digging itself into the bridge of the stud, it's not losing tension 
to the back length, we've pulled it over pitch and let it in and set 
the pin and all the proper things; we have learned all about 
elasticity at school and know for sure that the string has not been 
anywhere near it's elastic limit -- but it's stretching like a bit of 
plasticene.  This is a case where the craftsman cannot give the 
reasons.  He may know by experience exactly how sharp to leave the 
string in order not to need to return in a week, but he doesn't know 
why it happens.  This is one question I finally got the answer to 
from a Swiss physicist, a friend of mine, but there are lots of such 
questions following me about.

There are basic things like trigonometry which noone can design a 
piano without, but when it comes to the choice of the shape and 
material and grain direction of a piano bridge, then a host of 
questions raise themselves which need answers from all sorts of 
disciplines.  I could experiment with 200 varieties of hardwood in 
order to arrive at the best material by practical testing, but at the 
end I would still want to know why bubinga pseudoplatanus turned out 
to give the best results.  I would save a lot of time if I set out 
with various desiderata such as hardness, acoustic velocity, density 
etc. and then looked for a wood with the required characteristics and 
tested that.

Theory can never for me replace intuition and experience, but it can 
supplement them and get absorbed into them.  If you've ever tried to 
learn ancient Greek without the grammar, you'll know what I mean.

JD