Well, it seems that we simply do not agree. You didn't show any evidence that indicates that vibration is a one way street, just some completely erroneous references to Physics, which have nothing to do with vibrations resonating through the body.

This definition of resonance seems applicable here:
a : the intensification and enriching of a musical tone by supplementary vibration

If the body is transferring vibration from the strings, as it seems we agree about, why do you think that the vibrations only go one way and do not return any of that vibration back to the strings? That is a physical impossibility. If the body vibrates, it is impossible for some of that vibration to not transfer to the strings. I believe that is what resonance means (see above). Pickup a Strat, then pound on the guitar body with the side of your fist and see if your strings vibrate. Mine do, and I can feel them vibrating through the body after the rap on the body, resonance.

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Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.

When you pound on the body you are providing energy that can be transferred to the strings.

In normal playing, the body has no active energy source, so it just receives vibrations.
The vibrations it takes away from the picked strings (reduced amplitude at some frequencies) should affect what pickup "hears."

If there's any tonal differences between wood types, it would have to lie in differences in the amplitudes/frequencies affected.

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Member #26797
My other guitar is a Strat.

How the hell can they go both ways. A sound wave has a certain curve of arc, depending on it's frequency and depending on how you measure it (tool used) intensity. Whether that be a low note or high note.


The minute anything conflicts with that you produce varying levels of distortion. If you're clever you can achieve a doubling effect. By increasing or decreasing the number of cycles to the note over a set period of time, you change the pitch.

So what you describe is another conflicting sound wave both compressed (therefore out of pitch) and slowed in real time by the distance of it's travel. Then distorted by it's passing through multiple materials of differing density. (Which anyone who knows anything about sound proofing will tell you is the most common way of destroying a soundwave.) Acting on the original note. It in your mind will pass back through the guitar hit the source from where it originated whilst having remained completely intact? Sorry that cannot happen. Even if all the material along it's path was of the same density (which in this case it is firmly not), the time it would take is enough to render the note a jumbled mess. You'd really have to make every guitar with some super accurate predictions of your materials to achieve anything remotely playable.



Orville, in your instance there is still only a source and a result. The string then doesn't go on to affect the body, further affecting the string

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No no and no

Nikininja, I don't think I ever told you how well thought out your statments are. You certainly give a good argument, and back it up with fact. I would love to do a frequency test with maple and rosewood. But again, my ears tell me maple is brighter. I hope you do not take this as me "poking the fire", just wanted to compliment you.

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1965 Fender Precision Bass, 1994 Fender '54 Reissue Precision Bass, 2007 Applause Celebrity, 2011 Fender American Special Jazz Bass, 2012 Squier Vintage Modified Jazzmaster, 2013 Fender American Special Stratocaster, 2013 Gibson LPJ

Sounds reasonable to me.

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.

nikininja,

Toss a rock in a small pond or pool of water and watch the waves as they expand, hit the edge of the water and bounce back, crossing over the waves that are right behind, diminishing as they cross other waves and return to their origin and continuing the other way until diminished completely. Toss in a big enough rock and the entire surface of the water will eventually be full of waves bouncing all over the place, both primary and secondary, third and on, just like harmonics. Sound waves are an AC signal and the waves produced vary in amplitude and polarity, alternating from positive to negative.

A sound wave looks just like a sine wave (as in your illustration) or a water wave. So, by it's very definition, the AC will "go both ways", as your illustration shows. Secondary and third, and on, waves do not all interfere with the primary but add to the primary as in harmonics. So a "G" note could actual cause the body to resonate at some other frequencies at the same time as multiples of the original frequency, depending on the resonant frequency of the wood (or speaker cab for example). Any amount of body resonance at a different frequency than the original note can then influence the original vibration, adding to or taking away from it. Low resonance of the body, low influence on the strings, and also conversely a highly resonant body can add to the harmonic overtones that the strings produce.

I agree that any conflicting tones will add to distortion, and at the same time any that don't conflict can add to the harmonic content. But, I never used the term compressed to describe the affect of the finish on the sound, that was the OP. I would say that it dampens the sound, not compresses it. Maybe that's what he meant also? Two frequencies would have to be exactly 180 degrees out of phase with each other to cancel completely, anything less and they are overtones only partly diminishing or additive. This is figured into dimensions on a lot of musical equipment (like cabs) to prevent unwanted sound waves.

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.

I didn't say it does. I believe it's a one-way street, string to body.

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Member #26797
My other guitar is a Strat.

Rap on the body, strings vibrate, the vibration of the strings can then be felt resonating through the body with hand or ribs if held against your body. True or not? Of course it's true, that we can and did demonstrate. That's both ways folks, no matter how you slice it.

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.

> I believe it's a one-way street, string to body.

I wasn't clear enough, I guess. I meant the above "in normal playing" with respect to Niki's statement "the string then doesn't go on to affect the body, further affecting the string."

I can't say I do any rapping on the body while I'm playing. I agree, that if I did, I could probably cause a sound through my amps.

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Member #26797
My other guitar is a Strat.

Yes, the strings affect the body, the body affects the strings, it continues back and forth, not just there and back and done. Remember, sound waves are like AC, alternating, back and forth. Check the illustration that nikininja provided, the wave continues back and forth many times. And that particular representation is only a few cycles long, which is only mere milliseconds of time, the actual sound might last for several seconds having hundreds or thousands of those back and forth cycles until the sound diminishes naturally. So over time, the wave form would gradually get lower in amplitude til it fades out completely.

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.

To further illustrate the same effect of the strings on the body on the strings, etc, think of feedback from the amp causing the strings to vibrate, which causes more feedback building to whatever limits it, ie moving the guitar out of the influence of sound waves to diminish feedback, or lowering the volume. The obvious difference being that the amp produces sound vibration whereas the body can only conduct the waves produced externally, or resonate. So the "feedback" from the body is very weak in comparison to the feedback from the amp, so the amp has a much greater influence on the string vibration than does the body.

Edit:
For some reason, I could not post all of the above two posts in the same reply....? "Technical difficulties" error when I try all it in one reply, yet half would work fine. Strange.

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.

With the above argument over string vibration into consideration, I'd like to know what influence natural physics has on the way a guitar string vibrates. For example, what (if any) are the differences between the way a string sustains both in zero gravity and on earth, and what differences are there in soundwaves... will there be more sustain or less? what about wood vibration?

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Wow! I've heard of "Pigs in Space" but never guitars in space. Unfortunately sound waves cannot travel in outer space, as there is no medium for them to travel in. Maybe they have done experiments on the space station in an artificial environment? But gravity is one of the influences on string vibration. Remove gravity and you will get an increase in the sustain, not sure to what extent though, probably minimal as the other influences on vibration are much greater than the pull of gravity on a small string. But, check out Newton's laws of motion to understand the Physics of vibration or any type of motion. As far as we know, everything must follow Newton's laws of motion. One of the outside forces that act on a vibrating string would be the air itself. The string also loses energy by transferring some of the vibration to the other guitar parts attached to it, so the vibration would still diminish naturally even on the space station.

The "Law" of gravity, on the other hand, was believed to be wrong by Einstein, so that deserves further study by anyone interested. I am not sure if Einstein actually proved that the Law of gravity was wrong, but I believe him anyway. Maybe it is only the "theory" of gravity?

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.

Any of you tools actually play guitar? This site has jumped the shark...gone.

Just as a point of interest,Jimi Hendrix used to create a lot of his interesting feed back and harmonic effects by tapping the body,neck and even the springs in different places. BTW ratboy most of us tools have been playing guitar for much longer than you and maybe your Mommy and Daddy have been around.If the science and physics of what makes a guitar's tone is too much over your head and beyond your limited comprehension just go get your crayons and forget about it.

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'65 Strat,65 Mustang,65 Jaguar,4 more Strats,3 vintage Vox guitars,5 Vox amps,'69 Bassman with a '68 2-15 Bassman cab,36 guitars total-15asst'd amps total,2 vintage '60s Hammond organs & a myriad of effects-with a few rare vintage ones.