Is two better than one?

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KreherGuitars
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Is two better than one?

Post by KreherGuitars » Thu Jun 10, 2021 6:37 pm

So I recently got the box closed and got a nice peaky spectrum. Pulled out the ol’ signal generator for come chladnis and I have two monopoles and two cross dipoles... and they correspond to peaks on the spectrum. Any idea what is happening there? Are resonances coupling somehow?
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johnparchem
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Re: Is two better than one?

Post by johnparchem » Thu Jun 10, 2021 11:04 pm

Is one of the monopoles the back and one the top?

KreherGuitars
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Re: Is two better than one?

Post by KreherGuitars » Thu Jun 10, 2021 11:22 pm

Fraud not. I did a chladni on the back at 216

johnparchem
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Re: Is two better than one?

Post by johnparchem » Thu Jun 10, 2021 11:54 pm

I do not see a spectrum spike at 216 Hz. I am wondering if your back is pitched a bit below the top and the back is showing at 206 Hz and the top at 230 Hz. You can stick some mass on the top and/or the back (like blue tac) and see how the peaks move in relation to each other.

KreherGuitars
Beefwood
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Re: Is two better than one?

Post by KreherGuitars » Fri Jun 11, 2021 12:08 am

Ok I will try that to start. I suppose it’s possible. The back is built heavily. But the frequencies could be coupling when so close. Right?

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