As an exercise, I pose this question.  A cymbal has no definite
pitch, but it rings for a long time.  So it does not follow the 
rules below.  Why?


On Sat, 29 Nov 2014, Herbert Ward wrote:

>> But I invite all you proper physicists out there to explain why!
>
> I have a PhD in experimental physics.
>
> The term "resonant frequency" is a bit complicated.
>
> A string has a "resonant frequency" (its pitch).
> But a string's resonant frequency is obviously different from
> a lute's "resonant frequency".  For when I tap my lute, it does not
> ring at a specific pitch like (F# or Bb or 413.7 Hz).
>
> A lute's resonant frequency is very broad (I guess several octaves).
> A string's resonant frequency is very narrow (I guess 0.5 Hz).
>
> As the math works out:
>      lute   haves a broad resonant frequency  = short ring time
>      string haves a narrow resonant frequency = long ring time
>
> The physical difference is how much "damping" there here.
> You can google "damped harmonic oscillater" for more info.
>
> Many factors apply to both lutes and strings:
>     1. lighter = higher pitch
>     2. stiffer = higher pitch
>     3. heavier = lower pitch
>     4. looser = lower pitch
>
> As to why a smaller rosette makes a lower pitch, I'm not sure.  It
> might be simply because the is more mass in the soundboard  (#3 above).
> Or it might have be related to how wooodwind sound holes work.  Or maybe
> both.  An experiment to resolve the question would, I'm afraid, involve
> the destruction/degradation of the soundboard on a good lute.
>
>
>
> To get on or off this list see list information at
> http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html
>


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