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Discussion Starter #1 (Edited)
In a fully hollow bodied arch top guitar, how are the acoustic properties able to influence the sound/tone... vibrations of the top through the pickup(s)?
Or do they (i.e., is this a myth)?

This is a beautiful example of what I'm referring to...


This is might be more to the liking of others...


Thanks in advance. I have asked this question many times and have never been given much of a convincing (preferably scientific/acoustically based) answer.

Most often, I got blank looks or a short "Don't know" or "Beats me" from those that I expected would know.
 

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64 Gretsch 6120, 63 SG Standard, 62 Fender Princeton and a 58 Supro 1624T
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I'd be interested in a scientific answer as well. All I know is hollow bodies + my small ass studio = feedback!
 

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Huge influence. It's all about interaction between the components.
I’ll go write something long a boring and post it later.
 

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... All I know is hollow bodies + my small ass studio = feedback!
Not an expert on acoustic science by any means, but I suspect that this is part of the answer. The hollow body will resonate more readily and this probably translates to more sustain or otherwise affects the vibration of the strings, which is in turn picked up by the pick-up. I don't imagine that the vibration of the top is picked up as there is nothing metal to generate a current/magnetic field, however, it might possibly cause the pick-ups to vibrate relative to the strings (perhaps along a different plane or axis) which might also somehow affect the tone.

Interesting question!

Edit: I always tell my kids and students, "The only stupid question is one that you already know the answer to."
eg. "Should I practice more?"
 

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Both instruments shown have "floating" bridges. Such bridges will vibrate and emphasize those frequencies the vibrating top favors. The vibrating top will favour frequency ranges depending on bracing, body shape/size, wood properties, scale, etc. And of course, they will use the sort of tailpieces shown, to provide as little downward pressure of the strings on the bridge as possible, permitting the top to vibrate longer.

As always, remember that the steel string "wants" to come to rest after it is plucked. The harmonics produced, when the string is set in motion, will decline before the fundamental, such that the tone of the guitar will depend on how all the stuff noted above damps the harmonics over time-since-pluck. But of the top and body don't damp the string too much, the string will continue to vibrate for a while after the harmonics have died out.

Is that enough detail?
 

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Discussion Starter #7
Both instruments shown have "floating" bridges. Such bridges will vibrate and emphasize those frequencies the vibrating top favors. The vibrating top will favour frequency ranges depending on bracing, body shape/size, wood properties, scale, etc. And of course, they will use the sort of tailpieces shown, to provide as little downward pressure of the strings on the bridge as possible, permitting the top to vibrate longer.
This is now making it much easier for me to understand. Your explanations always have such clarity and flow so well.

Thanks very much!
 

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Discussion Starter #8
Is that enough detail?
I missed this in my last post.

The offer is much appreciated but please don't spend the time to type more detail. However, if you have a good link on this topic that you'd like to share, that would be wonderful.
 

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Take my answer with a grain of salt as I'm only surmising but a believe the pickups only pickup the string vibrations but the properties of the string vibrations are determined by the construction of the guitar.
 

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Discussion Starter #10
Take my answer with a grain of salt as I'm only surmising but a believe the pickups only pickup the string vibrations but the properties of the string vibrations are determined by the construction of the guitar.
That sums it up nicely.

I'm now feeling stupid for not being able to answer my own stupid question.

It all makes so much sense once you apply all of the factors that are interacting and apply some physics.
 
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Can you not shout into a pickup and it can pick up your voice? If so I think that will also allow some of the acoustic sounds to come through.

I have a Gibson 335, 137 and a custom jazz guitar. They do have more of an acoustic sound to them. Sort of on the fringes of the normal electric guitar sound. When played clean. When overdrive is on they also have a different tone than a solid body.
 

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I thought that was only possible with unpotted/minimally potted or microphonic pickups.
Try this, Dave (or anyone). On an amplified pickup, play something on your phone and bring the phone speaker close to the strings near the pickup, but don’t touch the strings. Observe in amazement :).
 

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You can shout into a pickup and hear it.

I did this on our last release, not sure if it made the cut...
 
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Actually, you shouted into the strings. The pickups in turn magnetically picked up the string vibrations resulting from your voice. Yes, I am a pedantic asshole :).
Well, I shouted into the pickups and that caused the strings to vibrate and the pickups did their thing. Also pedantic haha.

Another test would be yelling at the strings at 12th fret and noting what happens.
 
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Starting from the top, when a string is plucked (given energy), it vibrates in a series of nodes, collectively referred to as a mode. These change proportion and number, as the vibration (energy) decays. Although the initial energy was imparted in a particular direction (vector) via the pick, the polarity or plane of vibration rotates as it decays. This sweeps the acoustic environment of the instrument with energy, stimulating sympathetic resonances, particularly in hollow bodies. The resonant energy is coupled, or ‘heard’ by the vibrating string as it decays, influencing its mode of vibration. Just like the string’s vibrational modes, the body surfaces (particularly the top) also demonstrate vibrational modes wherein various portions of the wood serve as separate dynamic resonant zones coupled according to pitch. The physical makeup of the instrument reins over the net result of what one hears; body depth, width, flat/arch top, wood type/moisture/density/thickness, etc.
 

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When I had a tour through the former Gibson-now-Heritage-Guitars building in 1982, it culminated in being shown what was, at the time, the most expensive carved-top guitar Gibson made, the Kalamazoo Award ( Gibson Kalamazoo Award ). "Just breathe on it" my tour-giver said (I think, but don't know, that this was Marv Lamb, who became one of the co-owners/founders of Heritage). I did, and the strings resonated for a while. That was some responsive instrument.

So I have little doubt that if one shouts at a decently made archtop, equipped with a pickup, you can hear it. In the case of solid-bodies, any yelling-generated sound would, as Dave/Greco indicates, be a result of microphonic pickups.
 

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Discussion Starter #20
Thanks to everyone that has contributed to this thread.
I'm learning/consolidating the very interesting information and facts.
 
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