Questions re Main Air Resonance and Top Monopole

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Deems Davis
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Questions re Main Air Resonance and Top Monopole

Post by Deems Davis » Thu Feb 18, 2016 7:05 pm

I have been re reading the Design book and my mind is stumbling on visualizing something I'm hoping some of you can help with.

I understand that the Main Air resonance is produced by the 'air plug' that moves like a piston within the sound hole. And that it can be identified by tap testing with a spectrum analyser. So the frequency that is detected represents the oscillation of the air plug piston.

I also recall reading/seeing Chladni patterns that depict the Main Air resonance as a Monopole mode of the sounboard.

So am I correct to assume that the oscillations of the air plug are producing changes in the air pressure within the body cavity and those changes are transmitted to and manifested in the soundboard??? So that the 'sound' of the main air frequency is produced by the soundboard rather than the air plug?? (Elsewhere in the book it makes reference to the 1500hz peak with a discussion about how any frequencies below this are unable to escape via the sound hole).

Deems

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Trevor Gore
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Re: Questions re Main Air Resonance and Top Monopole

Post by Trevor Gore » Thu Feb 18, 2016 11:19 pm

See Section 2.4.1 and in particular Fig. 2.4-1.

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