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  #46  
Old 01-27-2021, 09:09 AM
charles Tauber charles Tauber is offline
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Originally Posted by Victory Pete View Post
Thanks for the replies, but I am convinced that what I am describing is of benefit for many reasons, one being tone.
Since you have convinced yourself that it is true it must be true.

Since it seems that any knowledge or experience contrary to that is irrelevant to your beliefs, Iíll refrain from further comment on your posts. Happy building.
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  #47  
Old 01-27-2021, 09:47 AM
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Originally Posted by charles Tauber View Post
Since you have convinced yourself that it is true it must be true.

Since it seems that any knowledge or experience contrary to that is irrelevant to your beliefs, Iíll refrain from further comment on your posts. Happy building.
The problem is your approach, I love science and technology, I hate jargon. You never can agree with anything I post. Let me ask you this: Do you think a flat soundboard would tend to sound bassy, responsive to fingerpicking and more prone to being lifted from string pressure? Also do you think an arched soundboard would tend to sound bright, less responsive unless strummed hard and less prone to being lifted from string pressure?
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  #48  
Old 01-27-2021, 01:53 PM
charles Tauber charles Tauber is offline
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Originally Posted by Victory Pete View Post
The problem is your approach, I love science and technology, I hate jargon.
I'm not going to go very far down that rabbit hole. However, science and technology are based on specific concepts, one of which is defining explicitly what terms mean.

Jargon is language that is used as a shorthand to refer to specific things amongst members of a group familiar with those things. Jargon can sometimes be used to purposely exclude those who are not members of that group.

By contrast, science uses terminology that is explicitly defined to describe key concepts that form the basis for understanding and discussing science. Sometimes, that terminology is used by laypersons who are unfamiliar with the precise definitions or use the terminology to refer to something else. A simple example is the word "stress". In colloquial speech, one might say, "I've had a really tough week and I feel stressed." Someone well-versed in science might say, "That beam is highly stressed." Same word, different meanings. When the term "stressed" is used in the context of a beam, it has a very specific, explicitly-defined meaning and isn't open to interpretation. Ditto for the term "bending stiffness".


Quote:
You never can agree with anything I post.
I'm sure we agree on some things.


Quote:
Let me ask you this: Do you think a flat soundboard would tend to sound bassy, responsive to fingerpicking and more prone to being lifted from string pressure? Also do you think an arched soundboard would tend to sound bright, less responsive unless strummed hard and less prone to being lifted from string pressure?
And, that's the point. The "response" of a guitar is the sum of many variables. There is very little that is proven to have a direct cause and effect that if I change this one variable, "this" response will result. It is very difficult to isolate a single variable so that it is the only one variable that is changed, allowing one to, with full certainty, create a cause and effect between that one change and the resulting response. If it were possible, we could write a single equation of known variables and choose the response we want and know exactly what to do - what values of those variables - to ensure that result. If we could, we'd be able to produce instruments with identical response, time after time. We can't. We'd like to, but we can't.

There are many, many variables involved in making a guitar, not the least of which is variation in the physical mechanical properties of the materials we use: wood. The "stiffness" (Young's modulus) changes from one piece of bracing material to the next, as it does from one guitar top to the next. The density - mass/unit volume - of the material changes from one piece to the next. The damping properties change from one piece of wood to the next. (The response of any mechanical system, including an acoustic guitar, is a function of the mass, stiffness and damping of that system.) So, when one attempts to isolate only the one variable of flat vs. arched top, one can't: other variables are also changing, muddying the waters of cause and effect.

Then there are issues of "strummed hard". As Alan alluded to earlier, how does one ensure that the "hardness" of strumming used to compare the flat top to the arched top. And so on, with more variables to control. If, for example, you play one "harder" than the other, consciously or subconsciously, or simply due to variations in muscular control, what does that do to one's conclusions of what influence flat vs. arched has on the response?

Anyone who wants to can, at any time, say, "I think this sounds better/louder/more balanced/(insert variable)." That isn't proof of anything. It's a subjective opinion. Anyone can express an opinion. There is nothing wrong with having an opinion or expressing one.

An opinion is something very different from an objective "fact". To substantially support something as being accepted as "a fact" or "true", science provides a specific methodology. That's what science is, a methodology, a way to approach the world and its phenomenon.

Something isn't true because one wants it to be, at least not from a scientific perspective. One can believe whatever one wants. By its very nature, belief doesn't require objective evidence to support it. That precludes statements such as yours, "I appreciate science and Wiki pages but I believe that my assertion is correct." Belief is the antithesis of science. (Belief is not the same as having a hypothesis.)

When you begin to use terminology that is explicitly defined in science, it implies an adherence to some semblance of scientific method. That method precludes something being true simply because one believes it to be true.

There is a difference between saying that, "pre-stressing a guitar top increases its stiffness", versus saying, "I think I get a sound I like better if I arch a guitar top." The first is presenting a cause and effect statement of purported fact, while the second is stating a subjective opinion or belief. One is an apple, the other an orange: one can't explain an apple using an orange and vice versa.

To be clear, there are many facets of life that are driven by belief - unsubstantiated opinion or faith. There is nothing wrong with that. The issue arises when people confuse belief with scientific "fact". Science can't prove a belief anymore than belief can prove science. They are parallel entities.

I'll conclude with three quotations that encapsulate all of the above.

"An art is a science with too many variables."
P.N. Adams, a fluid mechanics professor I once had

"Things should be made as simple as possible, but no simpler."
Albert Einstein

“A casual stroll through the lunatic asylum shows that faith does not prove anything.”
Friedrich Nietzsche

Last edited by charles Tauber; 01-27-2021 at 02:01 PM.
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  #49  
Old 01-27-2021, 02:59 PM
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Quote:
Originally Posted by charles Tauber View Post
I'm not going to go very far down that rabbit hole. However, science and technology are based on specific concepts, one of which is defining explicitly what terms mean.

Jargon is language that is used as a shorthand to refer to specific things amongst members of a group familiar with those things. Jargon can sometimes be used to purposely exclude those who are not members of that group.

By contrast, science uses terminology that is explicitly defined to describe key concepts that form the basis for understanding and discussing science. Sometimes, that terminology is used by laypersons who are unfamiliar with the precise definitions or use the terminology to refer to something else. A simple example is the word "stress". In colloquial speech, one might say, "I've had a really tough week and I feel stressed." Someone well-versed in science might say, "That beam is highly stressed." Same word, different meanings. When the term "stressed" is used in the context of a beam, it has a very specific, explicitly-defined meaning and isn't open to interpretation. Ditto for the term "bending stiffness".




I'm sure we agree on some things.




And, that's the point. The "response" of a guitar is the sum of many variables. There is very little that is proven to have a direct cause and effect that if I change this one variable, "this" response will result. It is very difficult to isolate a single variable so that it is the only one variable that is changed, allowing one to, with full certainty, create a cause and effect between that one change and the resulting response. If it were possible, we could write a single equation of known variables and choose the response we want and know exactly what to do - what values of those variables - to ensure that result. If we could, we'd be able to produce instruments with identical response, time after time. We can't. We'd like to, but we can't.

There are many, many variables involved in making a guitar, not the least of which is variation in the physical mechanical properties of the materials we use: wood. The "stiffness" (Young's modulus) changes from one piece of bracing material to the next, as it does from one guitar top to the next. The density - mass/unit volume - of the material changes from one piece to the next. The damping properties change from one piece of wood to the next. (The response of any mechanical system, including an acoustic guitar, is a function of the mass, stiffness and damping of that system.) So, when one attempts to isolate only the one variable of flat vs. arched top, one can't: other variables are also changing, muddying the waters of cause and effect.

Then there are issues of "strummed hard". As Alan alluded to earlier, how does one ensure that the "hardness" of strumming used to compare the flat top to the arched top. And so on, with more variables to control. If, for example, you play one "harder" than the other, consciously or subconsciously, or simply due to variations in muscular control, what does that do to one's conclusions of what influence flat vs. arched has on the response?

Anyone who wants to can, at any time, say, "I think this sounds better/louder/more balanced/(insert variable)." That isn't proof of anything. It's a subjective opinion. Anyone can express an opinion. There is nothing wrong with having an opinion or expressing one.

An opinion is something very different from an objective "fact". To substantially support something as being accepted as "a fact" or "true", science provides a specific methodology. That's what science is, a methodology, a way to approach the world and its phenomenon.

Something isn't true because one wants it to be, at least not from a scientific perspective. One can believe whatever one wants. By its very nature, belief doesn't require objective evidence to support it. That precludes statements such as yours, "I appreciate science and Wiki pages but I believe that my assertion is correct." Belief is the antithesis of science. (Belief is not the same as having a hypothesis.)

When you begin to use terminology that is explicitly defined in science, it implies an adherence to some semblance of scientific method. That method precludes something being true simply because one believes it to be true.

There is a difference between saying that, "pre-stressing a guitar top increases its stiffness", versus saying, "I think I get a sound I like better if I arch a guitar top." The first is presenting a cause and effect statement of purported fact, while the second is stating a subjective opinion or belief. One is an apple, the other an orange: one can't explain an apple using an orange and vice versa.

To be clear, there are many facets of life that are driven by belief - unsubstantiated opinion or faith. There is nothing wrong with that. The issue arises when people confuse belief with scientific "fact". Science can't prove a belief anymore than belief can prove science. They are parallel entities.

I'll conclude with three quotations that encapsulate all of the above.

"An art is a science with too many variables."
P.N. Adams, a fluid mechanics professor I once had

"Things should be made as simple as possible, but no simpler."
Albert Einstein

ďA casual stroll through the lunatic asylum shows that faith does not prove anything.Ē
Friedrich Nietzsche
TMI

"Things should be made as simple as possible, but no simpler."
Albert Einstein
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  #50  
Old 01-27-2021, 03:18 PM
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https://championingscience.com/2019/...20in%20science.
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  #51  
Old 01-27-2021, 03:32 PM
John Arnold John Arnold is online now
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I am going to try something different on the current guitar I am building. The top after being braced has a slight radius to it now. To guarantee it stays this way while gluing to the sides I am going to put in a threaded brace jack to keep this radius while I clamp and glue in the Gobar deck.
IMHO, that won't make any difference. My tops are built with a radius, but I clamp them using a flat piece of 3/4" plywood. They retain the radius. If your top is flatter after assembly on the rims, it probably means that it dried out after it was braced.
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  #52  
Old 01-27-2021, 03:35 PM
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Originally Posted by John Arnold View Post
IMHO, that won't make any difference. My tops are built with a radius, but I clamp them using a flat piece of 3/4" plywood. They retain the radius. If your top is flatter after assembly on the rims, it probably means that it dried out after it was braced.
I am not sure what happened to that one, My shop maintains proper humidity, but if it happens again I will try to jack it up before gluing to the sides. Do you mean your braces are radiused and you glue them to the top with a flat board?

Last edited by Victory Pete; 01-27-2021 at 04:00 PM.
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  #53  
Old 01-27-2021, 04:17 PM
John Arnold John Arnold is online now
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No. I glue the braces against a matching radiused surface. But when gluing the top to the sides, I use the flat plywood.
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  #54  
Old 01-27-2021, 04:42 PM
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Originally Posted by John Arnold View Post
No. I glue the braces against a matching radiused surface. But when gluing the top to the sides, I use the flat plywood.
Are your braces radiused? So you put the plywood on the top and then clamp?
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  #55  
Old 01-27-2021, 05:16 PM
mirwa mirwa is offline
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Originally Posted by charles Tauber View Post
Since you have convinced yourself that it is true it must be true.

Since it seems that any knowledge or experience contrary to that is irrelevant to your beliefs, I’ll refrain from further comment on your posts. Happy building.
I gave up page 1
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  #56  
Old 01-27-2021, 05:28 PM
charles Tauber charles Tauber is offline
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I gave up page 1
Wiser than me.
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  #57  
Old 01-27-2021, 07:35 PM
Glen H Glen H is offline
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At least itís all been civil! A rarity these days.
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  #58  
Old 01-28-2021, 06:23 AM
meredith meredith is offline
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Originally Posted by Victory Pete View Post
Thanks for all the info, it is a lot to contemplate. As far as the 1/2" critical measurement I was referring to, every acoustic I now have all have it, and they all have good volume and tone, except for one at one time, my 1998 HD-28. I had been shaving down the saddle years ago to get better action without realizing I was losing volume. At one point it had started to buzz at a party so I made a quick shim out of a popsicle stick. I was amazed at how loud it got. I attributed this to break angle only, I was unaware of the height of the saddle above the soundboard having a lot to do with it. So, for the 3 guitars I am building I made a block to show me exactly where to locate the bridge and determine the neck angle. right now the block is still high until I can get the exact dimension figured out. In the past I was shooting from the hip setting necks and they all came out good, they just varied a bit. I want dependable and repeatable results going forward. My Martin, now with a tall saddle, has the straightedge just hitting the top of the bridge with a little space due to the bridge rolling forward. I imagine 20 years ago there must have been quite a gap before the belly rose. That is why I am curious about this .094 spec I found in a video.
Today I learned where my Taylor's volume went.
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  #59  
Old 03-27-2021, 04:24 PM
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Default Neck Set Angle

I am doing another neck set soon. I took the strings off of my last build and took measurements. The height above the bridge is right where I had set it 3 months ago: .055". The action and other neck set parameters are perfect on this guitar so I am going for the same thing on my current build. The bridge I am using is Madagascar Rosewood and is a little bit higher so I am trying to compensate for that to get the same measurements as the previous guitar. I am not sure why most people here do not put as much or any distance above the bridge. It seems this would result in a very low saddle without the magic 1/2" string clearance to the soundboard. I was told Martin uses a measurement of .094" which seems like it would mean you would have very low action. I suppose a factor here is how high the bridge is to begin with. I can shave down the new bridge or have less saddle and break angle. The measurement from soundboard to straightedge is .425" if I figure for the finish as I glue neck and bridge before finishing.
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File Type: jpg 20210327_180758.jpg (25.5 KB, 48 views)
File Type: jpg 20210327_183958.jpg (30.9 KB, 46 views)

Last edited by Victory Pete; 03-27-2021 at 05:01 PM.
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  #60  
Old 03-27-2021, 05:35 PM
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Default Neck Set Angle Gauge

So I have what I have wanted for a while now. Regardless of the bridge I want to use, I have a way of getting the neck angle the same every time, This is assuming I have a top that has the same radius to it.
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