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  #106  
Old 03-08-2018, 08:09 PM
mmasters mmasters is offline
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My guess is Andy has played many guitars with his design and believes he is onto something. Not too different from myself, years ago I found placing guitars in specific colors for an extended period of time gave pleasing results. My results only worked best in my opinion with Adirondack spruce guitars though, placing them in a light blue color. His idea might work better with specific wood types and combinations as mine did.
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  #107  
Old 03-08-2018, 08:47 PM
robj144 robj144 is offline
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Originally Posted by mmasters View Post
My guess is Andy has played many guitars with his design and believes he is onto something. Not too different from myself, years ago I found placing guitars in specific colors for an extended period of time gave pleasing results. My results only worked best in my opinion with Adirondack spruce guitars though, placing them in a light blue color. His idea might work better with specific wood types and combinations as mine did.
Yes, but placing guitars in light is a lot different than changing the bracing.
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  #108  
Old 03-09-2018, 01:07 AM
Guitar Forest Guitar Forest is offline
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Originally Posted by Picker2 View Post
I really appreciate Andy’s extensive response and I thank you for asking permission to post it here. But a lot of what Andy writes does not make sense. Such as “undertones” at half the fundamental frequency of a string. Never heard of or read about them.

If I find time I might elaborate on Andy’s story and pinpoint the flaws. On the other hand, I might as well not.
Was this even worth posting?
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  #109  
Old 03-09-2018, 06:43 AM
Picker2 Picker2 is offline
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Originally Posted by Guitar Forest View Post
Was this even worth posting?
In retrospect, after posting a detailed explanation of my concerns regarding Andy's story in this very same thread: no.

I assume you missed it. Feel free to comment or ask for clarification.
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  #110  
Old 03-09-2018, 06:47 AM
Picker2 Picker2 is offline
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No need, I gave an example of what a response can look like. I did not want people to get an idea that everything is smooth and even and just maybe the peaks and troughs are something that Taylor is trying to get rid of. And as a far as I am concerned, if you do attain a very smooth and even response it can take part of the personality away from the sound. Might as well be playing a Les Paul. Without distortion.
The interesting thing is that if you tap the bridge with the flesh of your fingertip, and use that curve to perform a digital convolution, you get the sound of the string played with short/no nails.

However, if you tap the bridge with your fingernails (or a pick for that matter), you get the sound of the string played with fingernails or a pick.
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  #111  
Old 03-09-2018, 06:49 AM
mrgraveline mrgraveline is offline
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I think I side with Andy’s pseudoscience over your pseudoscience. Barely... but... I don’t buy your “tests” here at all.
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  #112  
Old 03-09-2018, 07:01 AM
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Originally Posted by mrgraveline View Post
I think I side with Andy’s pseudoscience over your pseudoscience. Barely... but... I don’t buy your “tests” here at all.
Well, Picker2's pseudoscience tests were free, sooooo......
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  #113  
Old 03-09-2018, 07:05 AM
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Just so I am understanding correctly you state AP's claim that if you pluck the E5 @ the 12 fret the guitar will also generate at 329 and 320 is not true .....
But you claim to offer proof of this by setting up a recording of the body resonance produced by tapping on the bridge, (which is not the condition or criteria stated by AP). The reason you give for recording the tap instead of the string pluck, does not stand up to objective analysis, and also has nothing to do with conditions in AP's statement . The reality is that ,,,,, at same time that you recorded the the bridge tap you could have recorded and graphed a string pluck at the 12 Fret E string and would have then actually and directly addressed the condition in the AP statement, you claim is not true .
It is always allowed to reach conclusions by scientific reasoning plus observations of one experiment to predict observations of another experiment - as long as you stick to generally accepted scientific principles.

In this particular case I don't get why AP stated that if you fret the high E at the 12th fret (659 Hz), the fundamental will also resonate (329 Hz). It doesn't, and it never will. That's the whole point of fretting a string. I assume it was just a slip of the pen, or maybe he meant it the other way around: if you hit the open E string (329 Hz) the first harmonic (659 Hz) will sound along with it. This is indeed true.

The recording of the body resonance after tapping the bridge may seem to be an odd thing to do, but it is a well-known method to capture the properties of acoustic systems (room ambiance, echo's, but also the tone of stringed instruments). The method is widely applied in digital audio processing, e.g., convolution reverb. It's a standard method and there are countless text books describing it.

There is no point in recording the string pluck to test the body resonance. The string pluck will only generate a very limited number of frequencies. It's like taking a picture through a couple of narrow slits - you will only see a small part of the total scenery. A short tap, however, generates all audible frequencies in one go and feeds them to the top. The top will then resonate with those frequencies it supports. Since the tap contains all audible frequencies, you can be sure you never miss one.

Regardless all of the above, my most important statement is that body resonant frequencies in a guitar are always so short and so unspecific that they will never interfere with the frequencies generated by the strings as they ring out. Since this is what the whole "better-in-tune-ness claim" of V-bracing is about, this claim makes no sense to me.
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  #114  
Old 03-09-2018, 07:07 AM
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Originally Posted by mrgraveline View Post
I think I side with Andy’s pseudoscience over your pseudoscience. Barely... but... I don’t buy your “tests” here at all.
:-)

It's not pseudoscience - it's not even science. These "tests" are very standard methods in digital audio engineering, applied every day by many. Any audio engineer and many others will confirm this.
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  #115  
Old 03-09-2018, 07:12 AM
drawshot1975 drawshot1975 is offline
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People make me giggle......

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  #116  
Old 03-09-2018, 07:12 AM
mrgraveline mrgraveline is offline
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I myself can confirm your tests are irrelevant to the questions at hand. I read all the “truths” on your website as well... many are just opinions that you label as truths. How about them crop circles, eh?
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  #117  
Old 03-09-2018, 07:44 AM
Picker2 Picker2 is offline
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Originally Posted by mrgraveline View Post
I myself can confirm your tests are irrelevant to the questions at hand. I read all the “truths” on your website as well... many are just opinions that you label as truths. How about them crop circles, eh?
If you don't want to provide me with any substantiation of your statements, which I would be happy to discuss further, we can also simply agree to disagree. :-)
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  #118  
Old 03-09-2018, 07:45 AM
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Originally Posted by Picker2 View Post
It is always allowed to reach conclusions by scientific reasoning plus observations of one experiment to predict observations of another experiment - as long as you stick to generally accepted scientific principles.

In this particular case I don't get why AP stated that if you fret the high E at the 12th fret (659 Hz), the fundamental will also resonate (329 Hz). It doesn't, and it never will. That's the whole point of fretting a string. I assume it was just a slip of the pen, or maybe he meant it the other way around: if you hit the open E string (329 Hz) the first harmonic (659 Hz) will sound along with it. This is indeed true.

The recording of the body resonance after tapping the bridge may seem to be an odd thing to do, but it is a well-known method to capture the properties of acoustic systems (room ambiance, echo's, but also stringed instruments). The method is widely applied in digital audio processing, e.g., convolution reverb. It's a standard method in digital signal processing, and there are countless text books describing it.

There is no point in recording the string pluck to test the body resonance. The string pluck will only generate a very limited number of frequencies. It's like taking a picture through a couple of narrow slits. A short tap, however, generates all audible frequencies in one go and feeds them to the top. The top will then resonate with those frequencies it supports. Since the tap contains all audible frequencies, you can be sure you never miss one.

Regardless all of the above, my most important statement is that body resonant frequencies in a guitar are always so short and so unspecific that they will never interfere with the frequencies generated by the strings as they ring out. And this is what the whole "better-in-tune-ness claim" of V-bracing is about.
I understand the scientific use of a tests of one thing to predict results of something else , in very specific instances , But there is no reason to do so in this particular case.

Of course there is a point recording the string pluck to test and verify the body resonance produced by plucking the E string at the 12 fret (the statement you claim is not true) and there is no logical reason not to , in order to prove or disprove AP's specific statement. It does not matter how many body resonant frequencies the string pluck will produce, because those frequencies are the only salient frequencies involved in AP' statement.

I may not have a degree in physics, but I have a Masters Certificate in Advanced Audio Production in Pro Tools and 15 years experience recording digital audio. So I am knowledgeable enough to know there is no logical reason not to use the same recording chain you used to record the bridge thump to record the string pluck . And your assertion that in this instance recording the tap will yield applicable results is flawed reasoning because it introduces unnecessary variables. Like the for example the bridge will not vibrate the same nor as long, as the string. The reality is that if you record the string pluck just like you recorded the tap, the resulting graph will show if there is any increased signal peaks below the E5 note . And might even prove you right .
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  #119  
Old 03-09-2018, 08:21 AM
Picker2 Picker2 is offline
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Originally Posted by KevWind View Post
I understand the scientific use of a tests of one thing to predict results of something else , in very specific instances , But there is no reason to do so in this particular case.

Of course there is a point recording the string pluck to test and verify the body resonance produced by plucking the E string at the 12 fret (the statement you claim is not true) and there is no logical reason not to , in order to prove or disprove AP's specific statement. It does not matter how many body resonant frequencies the string pluck will produce, because those frequencies are the only salient frequencies involved in AP' statement.

I may not have a degree in physics, but I have a Masters Certificate in Advanced Audio Production in Pro Tools and 15 years experience recording digital audio. So I am knowledgeable enough to know there is no logical reason not to use the same recording chain you used to record the bridge thump to record the string pluck . And your assertion that in this instance recording the tap will yield applicable results is flawed reasoning because it introduces unnecessary variables. Like the for example the bridge will not vibrate the same nor as long, as the string. The reality is that if you record the string pluck just like you recorded the tap, the resulting graph will show if there is any increased signal peaks below the E5 note . And might even prove you right .
OK, I see your point. Your proposed experiment will not provide additional information, but it probably gives better insights in this matter. And it's fun! So, especially for you , I went through the trouble to spend another three seconds, TWICE, to produce the measurements below.

This is the spectrum of the open E string of my Taylor GC BTO, plucked with my fingernail:



As you see, there is the narrow peak at 329 Hz (the fundamental), the first harmonic at 659, and many more higher harmonics. And... WAIT, there are 'subharmonics' too! One at 190 Hz and even one at 108 Hz!

Wrong.

These are not subharmonics. This is the fundamental resonant frequency of the guitar's top (108 Hz) and another resonant frequency of the top at 190 Hz. I can verify this by tapping on the bridge, this time with my fingernail:



See? There they are again, at exactly the same positions. As I explained earlier in this thread, plucking the string generates a shock wave in the string, which propagates through the string to the bridge. The effect of this is essentially the same as tapping the bridge. This causes the 'subharmonics' in the upper graph, except these are not caused by the string, but by the body. So they are not subharmonics, they are body resonances.

If you perform a real-time measurement of the plucked string, you will see that the body resonance peaks only last a short time. They appear, and are gone within half a second. The peaks caused by the string last as long as the string rings out - much, much longer.

This is the reason I conclude that body resonances don't 'fight' or interfere with the vibrations of the string. Because, and I repeat:

1. They last very short
2. They don't produce a distinct tone, but a 'thud' sound.

Stating that body resonances interfere with the 'in-tune-ness' of a guitar is like stating that the bass drum in a band interferes with the notes produced by the piano.
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  #120  
Old 03-09-2018, 10:34 AM
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Originally Posted by Picker2 View Post
OK, I see your point. Your proposed experiment will not provide additional information, but it probably gives better insights in this matter. And it's fun! So, especially for you , I went through the trouble to spend another three seconds, TWICE, to produce the measurements below.

This is the spectrum of the open E string of my Taylor GC BTO, plucked with my fingernail:



As you see, there is the narrow peak at 329 Hz (the fundamental), the first harmonic at 659, and many more higher harmonics. And... WAIT, there are 'subharmonics' too! One at 190 Hz and even one at 108 Hz!

Wrong.

These are not subharmonics. This is the fundamental resonant frequency of the guitar's top (108 Hz) and another resonant frequency of the top at 190 Hz. I can verify this by tapping on the bridge, this time with my fingernail:



See? There they are again, at exactly the same positions. As I explained earlier in this thread, plucking the string generates a shock wave in the string, which propagates through the string to the bridge. The effect of this is essentially the same as tapping the bridge. This causes the 'subharmonics' in the upper graph, except these are not caused by the string, but by the body. So they are not subharmonics, they are body resonances.

If you perform a real-time measurement of the plucked string, you will see that the body resonance peaks only last a short time. They appear, and are gone within half a second. The peaks caused by the string last as long as the string rings out - much, much longer.

This is the reason I conclude that body resonances don't 'fight' or interfere with the vibrations of the string. Because, and I repeat:

1. They last very short
2. They don't produce a distinct tone, but a 'thud' sound.

Stating that body resonances interfere with the 'in-tune-ness' of a guitar, like Taylor does, is like stating that the bass drum in a band interferes with the notes produced by the piano. (Hey, that's a good one! I'm gonna put it in a bold font. )
I appreciate your spending an additional 3 seconds doing a test just for me. So Thanks
And yes I see that the frequencies below the fundamental with a rise look to be in the same location as those with the bridge tap, which very interesting and speaks to your point . So I am guessing you are predicting the same would occur if you plucked the E string fretted at the 12
.. but we have only made it halfway to what I was suggesting . Where is the graph pluck with the E string fretted at the 12 th as per AP' statement ?
Kinda interesting to note the string pluck open high string you did does appear to generate the "Full spectrum" as you called it, and even produces rises below what the tap on the bridge does (which looks like "additional information") HUMMMMMM ????? It appears you were perhaps mistaken as to that being a reason not to test it . :


Also it's great that you bolded your statement but the inference in your statement does not appear to be what AP actually said....
To clarify .......What he said (according to what you quoted him as saying) was ------

Andy wrote:
As an example, the E5 note on the high string at the 12th fret has a frequency value of about 659 Hz. An octave below is the open high E string at 329 Hz. If a guitar has a natural resonance hot spot around 320Hz, it will vibrate whenever either of these E naturals are played. But what we’ll hear is a mix of 329 or 659 and 320. That’s going to have a detrimental effect on what we get to listen to.

I don't know or particularly care if what he is saying is true, but I am a bit of stickler for refuting what is actually said.


BTW I have been meaning to mention your "White Lighting" piece is outstanding
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Last edited by KevWind; 03-09-2018 at 11:56 AM.
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