What would you call these modes

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What would you call these modes

Post by kiwigeo » Tue Sep 18, 2012 9:34 am

Two interesting Chladni patterns I snapped while doing tests on my falcate braced classical. At higher frequencies the nodes seem to follow the bracing more than at lower frequencies. Any idea what youd call the modes in the photos below?
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Trevor Gore
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Re: What would you call these modes

Post by Trevor Gore » Tue Sep 18, 2012 10:54 am

kiwigeo wrote:Any idea what youd call the modes in the photos below?
Punch and Judy?

There are endless shape permutations as you go higher up the frequency range, many of which are difficult to categorise under the usual nomenclature systems, and some that you'll never see again. A generic name I've heard is multi-lobe modes.

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Re: What would you call these modes

Post by kiwigeo » Tue Sep 18, 2012 11:17 am

The top one reminds me of one of your equations.......therefore I shall call this mode "Trevor".
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Re: What would you call these modes

Post by kiwigeo » Tue Sep 18, 2012 12:18 pm

The other mode is on the backside of the guitar so I shall name it.......Kim. :mrgreen:
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Re: What would you call these modes

Post by Dominic » Tue Sep 18, 2012 10:12 pm

Nice set up to get such clean lines at those high frequencies Marty. I wonder if there is a frequency that would outline all the braces?. You got a ubeaut analogue one from that guy didn't you? My sig gen works great but I only have a shitty little component amp and need something cleaner and more powerful.

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Re: What would you call these modes

Post by kiwigeo » Wed Sep 19, 2012 7:51 am

Dominic wrote:Nice set up to get such clean lines at those high frequencies Marty. I wonder if there is a frequency that would outline all the braces?. You got a ubeaut analogue one from that guy didn't you? My sig gen works great but I only have a shitty little component amp and need something cleaner and more powerful.

Dom
Hi Dom,

Yes there was one mode I got that pretty much outlined all the top bracing quite nicely. The signal generator is a Bradley I got from the US. Its got a 50 watt amp built in and Im using a fairly large speaker as well.
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Re: What would you call these modes

Post by ScottC. » Tue Nov 13, 2012 4:49 am

I came across this chart, I don't know if you have seen this
http://en.wikipedia.org/w/index.php?tit ... svg&page=1
My excuse is "I'm new"

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Re: What would you call these modes

Post by ozwood » Tue Nov 13, 2012 6:32 am

The top one reminds me of one of your equations.......therefore I shall call this mode "Trevor".
:lol: :lol: :lol: :lol: :lol: :lol: :lol:


Love it ! :cl
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Re: What would you call these modes

Post by Trevor Gore » Tue Nov 13, 2012 4:44 pm

ScottC. wrote:I came across this chart, I don't know if you have seen this
http://en.wikipedia.org/w/index.php?tit ... svg&page=1
I hadn't, but it looks like free plate modes, which I've never found particularly useful, though some people do. There's lots of other such diagrams in Fletcher and Rossing and more pics here.

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Re: What would you call these modes

Post by ScottC. » Wed Nov 14, 2012 1:51 am

I don't know what they mean, maybe someday I'll make some sense of them?
Thanks, Scott C.
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Re: What would you call these modes

Post by charangohabsburg » Wed Nov 14, 2012 4:26 am

trevtheshed wrote:
ScottC. wrote:I came across this chart, I don't know if you have seen this
http://en.wikipedia.org/w/index.php?tit ... svg&page=1
I hadn't, but it looks like free plate modes, [...]
I agree, it looks like that, and I discovered that it actually was used to illustrate free plate modes (here, on German wikipedia).
trevtheshed wrote: [...] which I've never found particularly useful, though some people do.
ScottC wrote:I don't know what they mean, maybe someday I'll make some sense of them?
I think that mainly "violin people" find free plate modes useful, which makes sense because they can pop off tops or backs and reassemble the instrument without damaging it in the process, which allows to discover relationships between the free modes and the sound of the finished instrument. I believe that with a guitar, taking off the top and putting it on again involves too many steps that compromise the integrity of the involved parts (first of all the top itself, but also the linings, binding and purfling, where the latter ones may or may not have a perceivable impact to the final result).
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Re: What would you call these modes

Post by ScottC. » Wed Nov 14, 2012 4:53 am

I thought they would be useful to somebody!
My excuse is "I'm new"

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