Body Movement/flex In Guitars

[guitar_ed]

Hi,

I found this web site by accident, while I was looking for something else. It is by a guy from Kettering University in Flint, Michigan. It addresses how the bodies of guitars move and flex while being played. It is very interesting, actually. Guitar Movement & Flex

I brought this up because from time to time people ask about the influence of body shapes, etc.

Guitar Ed

[thedoctor]

I knew it, I knew it, I knew it! There it is in all it's glory! I knew the sound was most controlled by the NECK!! I could just kiss those guys!! Really, I could! What a GREAT piece of research!!!!

[RGGR]

I knew it, I knew it, I knew it! There it is in all it's glory! I knew the sound was most controlled by the NECK!!

Eh?!.....I read the articles provided in the link......but I'm not really sure I can locate the part that says the sound was mostly controlled by the NECK.

[crafty]

Funny how the study was funded by Gibson, yet there's a picture of a PRS on the link to the Epiphone Coronet test.

Also, just a side note, Kettering used to be known as GMI, or General Motors Institute. GM still owns most of the university and trains the best automotive engineers in the world there, including the ones that wind up working for Toyota, Nissan, Honda, Ford, and DaimlerChrysler.

[Mickguard]

I knew it, I knew it, I knew it! There it is in all it's glory! I knew the sound was most controlled by the NECK!! I could just kiss those guys!! Really, I could! What a GREAT piece of research!!!!

←

I don't get this either--where do you see the conclusion about the neck?

All I get out of this is that guitars vibrate differently according to the frequency of sound (now THERE's a surprise!)...

But there are way too many uncontrolled variables in this 'experiment'. They could better take the same neck, for example, and bolt it on various body shapes made from the same type of wood (difficult to control, the wood would all have to come from the same tree). Then they could take the neck and bolt it on various types of wood in the same body shape.

And not only that, they're not testing vibrations in PLAYING POSITION.

This is just a dorky student experiment designed to teach students about using testing equipment using props the students will think is 'cool' in order to hold their interest long enough to stop them from checking their SMS messages every two minutes. There are no valid scientific conclusions to be drawn from this.

[crafty]

We will be measuring the input mechanical impedance at the bridge to determine how much string energy is lost to vibration of the body. This is bad, because if the body vibrates the strings cannot sustain as long as they should.

That was a quote from the Explorer page. It appears that at higher frequencies, the body began to resonate and absorb the vibrations more than the neck. More mass dampening the vibrations equals less sustain. You want the neck to vibrate more than the body because it is less likely to dampen the sound and sustain.

The research on the acoustic guitar was very interesting, too. It showed just how important the back of the guitar is at higher frequencies.

[Moreau]

Even if the wood was all from the same tree, it wouldnt be controlled. wood is so different. youd would have to use the same neck. but im sure that this study would be a good area to start more specific testing, if someone were ambitious enough to do so