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Location: ms | I have a headache :( |
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Location: Scotland | Going back to basic acoustic physics in relation to body size. A guitar is basically a helmhotz resonator. When Helmholtz theory is applied to guitar design it's about the size of the air-cavity in relation to the size of the soundhole(s). This produces the fundamental frequency of the instrument. There is an optimum soundhole size for a given body size, and changing either will raise or lower the fundamental. This is partialy why single epaulet Adamas/Etlite T's are so highly regarded. It's also how airlocks and feedback bungs work. If you want an example of Helmholtz Theory in practice compare the acoustic sound of your guitar with and without airlocks or a feedback buster. With the bungs in the acoustic output changes only slightly but the bass is reduced because the fundamental frequency has been raised. Those of you with Elites/Adamas play your guitar with the back-plate off and see what happens. Fun with acoustic physics!
Incidentally, Ryan has started making guitars with ports in the rim! So much for "Reflecting towards the soundhole"
Acoustic "flutes" |
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Location: Capital District, NY, USA Minor Outlying Islands | Helmholtz a theory? It's a Helmholtz Fact Jack!
Heir Helmholtz.
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Location: South of most, North of few | Paul, I saw the guitars he makes with the rim ports and have seen similar designs in other makes. I think someone here even drilled an Elite in the upper bout for a sound port. I have played my Adamas and Elites without the rear cover. It sounds like you've lost most of the guitar! Thanks for the insight. |
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| I wish someone would utilize all this new, scientifically proven, information and create a guitar an acoustic guitar that focuses the sound waves toward the top so we can all listen to it and be amazed!
Randy |
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Location: Warren,Pa. | Jim,
I'm the one who drilled the "sound ports" in my Elite. They work nicely, but at present I have the OpPro removed to borrow parts for another guitar. With the added hole where the OpPro was, the sound is pretty thin. It was just "dumb luck" that the holes I drilled didn't ruin the sound. Opening up the preamp hole pushed it over the edge. In tap-tuning a guitar top I believe they call this the "point of dispersion".
John <>{ |
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Location: South of most, North of few | Yeah John, I remember now. (old age) You did a really nice job on it too as I recall, multi hole configuration, like the top. |
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Location: Colorado Rocky Mountains | Doesn't a violin provide further evidence of the theory that the dynamics of a vibrating top are more important to sound volume than the size and shape of the instrument cavity? Isn't this why a violin soloist can soar above a full orchestra without amplification (strings, bridge, bow technique, etc. notwithstanding)? |
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Location: Scotland | Originally posted by Northcountry:
I wish someone would utilize all this new, scientifically proven, information and create a guitar an acoustic guitar that focuses the sound waves toward the top so we can all listen to it and be amazed!
Randy Ok, there are two basic ways to stop a soundwave: either absorb it (as used in acoustic treatment of recording spaces) or put something massive in it's way, which would in effect reflect some or all of the wave back towards it's source and/or diffuse it an random directions. For a surface to reflect a soundwave effectively it's resonant frequency must be lower than the soundwave, or the soundwave sets the surface in motion while passing through it. This is known as the "drumhead effect" and is one of the reasons why sound, especially low frequency, tavels well in internal domestic house construction, which is usually 2 X 4 stud and gyproc. You can't easily make a rigid structure with lots of mass from relatively lightweight flexible materials, and it takes mass and rigidity to stop or reflect LF.
In order to have a theoretical guitar where most or all of it's sound is reflected back to the top, the back and sides would need to be so dense, thick and rigid that you probably wouldn't be able to lift the thing. |
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Location: Jet City | Originally posted by Weaser P:
as I was sitting here on a Sunday afternoon with a small glass of Cab And that's about the only thing I can relate to and understand in this thread.
In layman's terms, can anyone tell me why my Elite LX is so much quieter than other acoustics when I'm playing acoustically? My guitar just doesn't come out in the mix. I find I grab my Washburn just to compete volume wise. I hear myself fine, but others struggle to hear me.
Maybe I need a different O. I was wondering if it was due to not having the round hole. |
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Location: Boise, Idaho | Don't feel all alone, Damon. I've been trying to figure out how the guy who invented the manuever to stop people from choking has anything to do with soundwaves. If you pick the guitar up and squeeze it really hard just above the waste, do you force more sound out the soundhole? |
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| You stand more chance if you spell it waist.
Ignore all the mystical bollocks from The Man Of The Year - he swapped living in England for living in Scotland and plainly cannot be trusted. |
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Location: East Tennessee | Originally posted by schroeder:
You stand more chance if you spell it waist.
He was trying to spell like you Brits spell. :D |
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Location: Boise, Idaho | I was actually concentrating on spelling maneuver and screwed that up too. Don't think Shreodur cought that one, though. |
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Location: South of most, North of few | Good one Mark! :D |
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Location: Boise, Idaho | Those Brits use words like "bollocks" so no one can check on their spelling. My dictionary does have "bullock" though. It's a castrated bull. Is that the same thing, Schroeder? |
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Location: enid, ok | This whole post is bullocks. |
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Location: Cicero, NY | Sandra? That belongs in that other thread... |
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He said it.
