SW heresy?

[Horace Greeley]

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Sarah,

Now, thar ya' be goin' agin with all that there thinkin' and observin' and 
such....doncha know that's where all the trouble starts?

Horace


At 10:30 PM 8/21/2004, you wrote:
>Hi all,
>
>Thanks for the advice about techniques to even out the SW curve!  That 
>should give me a variety of techniques to use/combine in order to even out 
>the jags.
>
>But the question is one of what my target curve should *really* 
>be.  Hmmmm....  My thoughts:
>
>The unmodified SW curve is obviously very linear.  (Yes, I know what 
>linear means.  I "minored" in mathematics, sort of -- except that my U. 
>didn't officially recognize minors).  Stanwood's curves, OTOH, are all 
>concave downwards.
>
>I was advised off list that I shouldn't force the hammers to artificially 
>conform to a standardized Stanwood curve but to simply even out the jags 
>to make the action smooth from bottom to top.  There's something to be 
>said for this idea.
>
>But as I got to thinking about the SW curves, I was wondering, where do 
>they REALLY come from?  That is, where does the shape come from?  I 
>suspect the hammer manufacturing people might be able to enlighten me as 
>to this.  (Ray???)  I'm *guessing* that the felt is denser than the 
>molding, and when the hammer becomes skinnier, it loses more felt than 
>molding, resulting in a more precipitous dropoff in weight at the higher 
>end.  This would occur with a constant hammer length and a linear 
>variation in hammer and molding (and felt) width.  Am I anywhere close on 
>this idea???
>
>Contrast this function with other functions that might actually relate to 
>optimal hammer mass:  String length and mass both decrease with the note 
>number, with a function that is concave upwards.  Note frequency increases 
>with a function that is concave upwards.  Note period (inverse of 
>frequency) increases with a function that is concave upwards.  The 
>Stanwood curve seems rather meaningless with regard to any of these 
>functions.  For instance, it might be good to match hammer mass to string 
>mass by some proportion.  Right?  As the scale goes up, string length and 
>mass approach an asymptote of zero.  Therefore, shouldn't hammer mass 
>approach an asymptote of zero?  Instead, the curve starts taking a dive in 
>the treble.  If the scale went up well past 88, hammer mass would 
>eventually crash to zero.  Because these curves do not have the same form, 
>the relationship between hammer and string mass is anything but 
>constant.  That doesn't make sense.
>
>So is this something that is the way it is just because of tradition -- 
>because the cauls are built that way, and that's what ya' get?
>
>Now that I look at my linear SW curve (with jags), I'm wondering if this 
>isn't REALLY a closer match to something meaningful (like string mass) 
>than the idealized Stanwood curves.  Any thoughts, y'all?
>
>Peace,
>Sarah
>
>
>

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