[CAUT] String Coupling / SB and Bridge stiffness...and maybe Pure Sound

[Porritt, David]

Fred:

And then we have the ones who claim that a unison can be too clean and they alter it.  Having never tuned - nor even heard - a unison I thought to be too clean I'm jealous of anyone who can produce one of these.

dp


David M. Porritt, RPT
dporritt at smu.edu

-----Original Message-----
From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On Behalf Of Fred Sturm
Sent: Sunday, June 14, 2009 1:55 PM
To: caut at ptg.org
Subject: Re: [CAUT] String Coupling / SB and Bridge stiffness...and maybe Pure Sound

On Jun 14, 2009, at 5:24 AM, Richard Brekne wrote:

> I'll turn your other reasoning around on you just for the sake of  
> making a point.  We could just as easily say  "It is a hard concept  
> for piano techs to accept that it DOES make a difference since we   
> have invested so many resources in acquiring and using ETDs, and  
> find so many easy shortcuts in their use that provide large amounts  
> of motivation to justify saying... it doesn't matter".
>
> Let me stretch the point just a bit further... in perhaps a bit over  
> obvious direction but one that illustrates my point. At this stage  
> in keyboard development and for the greatest percentage of  
> listeners... most can not discern the difference between the  
> keyboard and an acoustic piano. So really.. by the same reasoning it  
> really doesn't matter whether we use a Clavinova, or a piano... with  
> rare exception.


Hi Rik,
	For me it is a question of where to put emphasis, what is most useful  
to obsess about. In tuning, I find I obsess more and more on unisons.  
Going back to some of the early subject matter in this thread, to  
string coupling, I'd say that while coupling occurs, there is a  
difference between a coupled unison and a true unison, and it is both  
apparent to the ear and to the ETD (though sometimes there needs to be  
some interpretation of the ETD output or fiddling with position of the  
devise relative to the strings). Coupling could be said to be the  
point at which "beating stops." Which means that there aren't any full  
"loud soft" cycles. There is, however, still an interference pattern,  
and we hear it as a wow (to try to put it in letter form. I think we  
all know what the sound is). Then there is the point where all that  
wow disappears, and the unison is completely clear.
	Now if a whole piano is tuned with all unisons as close as possible  
to what I describe as completely clear, the sound of the instrument is  
pretty dramatically different from an instrument where there is still  
some wow in many if not most unisons. I think that difference is quite  
a bit greater than what can be achieved by fooling around with  
tweaking the placement of pitches relative to one another. Always  
assuming a reasonable  set of parameters as a starting point.
	I am quite aware that many people swear by many subtle alterations of  
pitch "by aural means" and others swear by their own formulae of non- 
equal. It's a controversial topic. The position I am taking is quite  
naturally subject to the criticism you offer: "I am saying it doesn't  
matter, hence I am saying that nothing matters" (to take it to its  
logical conclusion). But, hey, I have a fairly tough hide and can take  
it. In any case, I am certainly not saying "nothing matters," but  
simply putting priorities where I think they really lie. With respect  
to tuning, I think unisons, and every single unison on the piano, are  
by far the biggest factor, and tend to be discussed far less than this  
or that magic formula for temperament and/or stretch.
Regards,
Fred Sturm
University of New Mexico
fssturm at unm.edu