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  #46  
Old 03-08-2018, 03:46 AM
mrgraveline mrgraveline is offline
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Easy to see who doesn’t feel comfortable in this thread that some guitar builder for Taylor might have greater knowledge than they do.

Andy laid it all out there, for sure. Any one claiming “marketing bs” has less of a claim. Now I just hope they sound as good as the effort and science that went into them.
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  #47  
Old 03-08-2018, 06:18 AM
Picker2 Picker2 is offline
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Quote:
Originally Posted by Bill Yellow View Post
Undertones in a resonating body are real. The church bell is the textbook example, where we hear a low drone somewhere near a major 6th below the Bell's fundamental resonant frequency.
So why don’t you call that “undertone” the fundamental resonant frequency then? It’s just a matter of your definition. For me, the fundamental is the lowest frequency a mechanical structure can support.

It is indeed true that a guitar body can generate resonant frequencies lower than the fundamental frequency of a string, but as I explained in an earlier post in this thread, this will not affect intonation.
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  #48  
Old 03-08-2018, 06:25 AM
rgregg48 rgregg48 is offline
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If you can't Dazzle them with your brilliance, baffle them with your bull!
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  #49  
Old 03-08-2018, 07:42 AM
Shades of Blue Shades of Blue is offline
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Glad to see Andy finally explain in depth, and it made sense to me for the most part. I think it is like watching HDTV. Sometimes getting the picture "perfect" can backfire and allow you to literally see everything, intended or not. Sometimes I like watching movies in standard definition to get the full effect.
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  #50  
Old 03-08-2018, 08:10 AM
Purfle Haze Purfle Haze is offline
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Quote:
Originally Posted by gitarro View Post
You could say it was perfectly balanced in every way but if it is too coherent and in phase, it can end up sounding lacking in colour.

Therefore i wonder if it may not be wholly desirable to have a top that vibrates too uniformly. Could it be that the chaos who is seen as the enemy by the v class bracing school is the very thing that helps make the tone interesting?
In the end, I suspect Gitarro may be right; that Taylor may engineer what we love about guitar tone out of their instruments. Time will tell.
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  #51  
Old 03-08-2018, 08:18 AM
ronadair ronadair is offline
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Andy Powers certainly deserves credit for the detailed response. That had to take a while to write. Sounds smart & well reasoned.
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  #52  
Old 03-08-2018, 08:24 AM
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V Brace in a nutshell.

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  #53  
Old 03-08-2018, 08:27 AM
kcnbys kcnbys is online now
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Quote:
Originally Posted by Purfle Haze View Post
In the end, I suspect Gitarro may be right; that Taylor may engineer what we love about guitar tone out of their instruments. Time will tell.
According to all those who think Taylor's are "too bright" and "sterile", it seems they already did that a long time ago. The revamps of Taylor Guitars over the last several years won some of those people over to the brand, but not most. V-bracing won't dramatically change who is buying Taylor's, and based on Taylor's immense popularity and market share, it really doesn't need to. TG are innovators, and they always will be; it's just who they are. If you like them, play them. If you don't, don't. The people who can't accept Andy's answer, already had their minds made up.
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  #54  
Old 03-08-2018, 08:40 AM
Shades of Blue Shades of Blue is offline
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Originally Posted by Purfle Haze View Post
In the end, I suspect Gitarro may be right; that Taylor may engineer what we love about guitar tone out of their instruments. Time will tell.
I don't know if that is really possible, but I know what you are saying. I think that once these guitars are out on the market a while, people will reinforce their opinions on Taylor one way or the other.

For example, I tend to hear more "strings" than wood in Taylor guitars. To me, ultra clarity isn't what I want to hear and it leaves a lot of the "meat" I want to hear off of individual notes. I imagine that V Bracing will only reinforce that clarity that I don't really like in the first place.

Make sense? I doubt it does because what I hear is unique to me as an individual. People will undoubtedly LOVE the new Taylors, and that is a great thing and I wish them all the best. I'm just happy I found two Martins that make me happy enough that I don't have to fool around with Taylor anymore
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  #55  
Old 03-08-2018, 08:48 AM
Picker2 Picker2 is offline
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Quote:
Originally Posted by Herb Hunter View Post
I note that though you say, "a lot of what Andy writes does not make sense,” you only list one item. Given that statement, it seems to me that you are obliged to list more than but one nonsensical example.
OK Herb, I'm picking up the glove. Here we go.

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.

This is simply not true. The E5 note on the high string at the 12th fret has indeed a frequency value of about 659 Hz. But this is the lowest frequency the string will generate. Along with the 659 Hz, it will also produce many higher harmonics, all at different amplitudes, at integer multiples of 659 Hz. The open high E string will not resonate at 329 Hz, because the string is fretted at the 12th fret. If the guitar has a natural resonance hot spot around 320Hz, it is true that it will resonate when the E5 is played, but only for a very short time! The 659 Hz of the E5, while ringing out, will not excite the 329 Hz body resonant frequency. So you will not hear "a mix of 329 or 659 and 320Hz" like Andy stated, but only the 659Hz with its harmonics, along with a very short signal around 320 Hz, which has such a wide spectrum that it will not be perceived as a tone, but rather as a 'thud' sound.

The reason that the 320Hz only resonates for a short time, producing the 'thud' sound, is because it is a body resonance, not a string resonance. It is excited by the attack of the string (the 'pluck', if you will). This attack will send a shock wave through the string with a very broad frequency spectrum. It basically contains all audible frequencies, which will run through the string to the bridge and to the top of the guitar. The guitar top receives all these audible frequencies at the same time, but will resonate only along with a few of them. These are the resonant frequencies, and these create the short 'thud' sound, very similar to what you hear when you tap with your finger on the bridge. It's basically the same thing.

You can easily measure the resonant frequencies of your guitar. I just did it for my Taylor BTO GC Cedar/Walnut. Simply tap the top, and measure the frequency content with a simple spectrum analyser app (I used an app called Analyzer, for iPhone). It took me about 3 seconds to produce this:



As you see, there is a resonant peak at 106 Hz, something at 180, a small one at 570 and a few other very small ones. These frequencies are indeed the 'tones' you hear when you tap the top of my guitar (they're different for every guitar). This is the 'thud' sound I referred to earlier, and this is the same 'thud' sound you hear after you pluck any string. Try it out yourself: plucking a string creates a sound as if you tap the top - after which the string will ring out.

However, as you can see from the graph, the resonant peaks are quite wide. This explains why you hear a 'thud' and not a clear tone, which would happen when you tap against a wine glass:



As you see, the spectrum of a wine glass has a much narrower peak, and therefore you hear a clear tone when you tap it, just like a church bell.

So yes, if a guitar body had similar resonance characteristics as a wine glass, then Andy Powers would have a point. Every time you would pluck a string, any string, the attack would produce a clear 'pinnnggggggg' tone, not a 'thud', which would probably be dissonant with the notes you played. But as we all know, the guitar will only produce a 'thud', with a wide spectrum, which lasts only very short, so it does not interfere with the intonation of the guitar, nor does it produce 'warbly' tones or 'fights'. It simply does not happen.

Another erroneous statement by Andy is: "...since guitar strings do not introduce pure sine wave signals, but multi-frequency content ... When you sum these things together, you end up with a surface that resembles wrinkling tin foil...".

I know where he is going to, but he is mistaken. A vibrating guitar top does not look like wrinkling tin foil, but always vibrates in quite an orderly fashion, even for the high frequencies. Its behaviour is identical to the vibrational modes of a guitar string (albeit in 2 dimensions). Just like a guitar top, a vibrating guitar string also contains a plethora of different frequencies, all happening at the same time at various wavelengths. However, the vibrating string does not look like a wiggly chaos of all kind of different waves happening at the same time (the one-dimensional version of wrinkling tin foil): it essentially looks like a simple and orderly polygon all of the time. You can see this below in a computer simulation I wrote a while ago, which simulates a vibrating guitar string and the sound it produces depending on where it is picked:



It is true that the polygon contains many kinds of different frequencies, but they all add up to make just a simple polygon. A guitar top does something similar, albeit in two dimensions.

However, the most disturbing point about Andy's story, in my opinion, is the fact that he only tells that V-bracing solves all the alleged intonation issues, but he never explains how it does such a thing. Why would V-bracing systematically shift all resonance frequencies towards positions where they are "more in tune" with the strings? How can you reproduce this effect on mass-produced factory guitars? If it works so reliably, there must be a very fundamental principle underneath it. But Andy fails to make this clear - in fact he does not even mention it. I think that is disturbing.
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  #56  
Old 03-08-2018, 09:17 AM
Shades of Blue Shades of Blue is offline
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Quote:
Originally Posted by Picker2 View Post
OK Herb, I'm picking up the glove. here we go.

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.

This is simply not true. The E5 note on the high string at the 12th fret has indeed a frequency value of about 659 Hz. But this is the lowest frequency the string will generate. Along with the 659 Hz, it will also produce many higher harmonics, all at different amplitudes, at integer multiples of 659 Hz. The open high E string will not resonate at 329 Hz, because the string is fretted at the 12th fret. If the guitar has a natural resonance hot spot around 320Hz, it is true that it will resonate when the E5 is played, but only for a very short time! The 659 Hz of the E5, while ringing out, will not excite the 329 Hz body resonant frequency. So you will not hear "a mix of 329 or 659 and 320Hz" like Andy stated, but only the 659Hz with its harmonics, along with a very short signal around 320 Hz, which has such a wide spectrum that it will not be perceived as a tone, but rather as a 'thud' sound.

The reason that the 320Hz only resonates for a short time, producing the 'thud' sound, is because it is a body resonance, not a string resonance. It is excited by the attack of the string (the 'pluck', if you will). This attack will send a shock wave through the string with a very broad frequency spectrum. It basically contains all audible frequencies, which will run through the string to the bridge and to the top of the guitar. The guitar top receives all these audible frequencies at the same time, but will resonate only along with a few of them. These are the resonant frequencies, and these creates the short 'thud' sound, very similar to what you hear when you tap with your finger on the bridge. It's basically the same thing.

You can easily measure the resonant frequencies of your guitar. I just did it for my Taylor BTO GC Cedar/Walnut. Simply tap the top, and measure the frequency content with a simple spectrum analyser app (I used an app called Analyzer, for iPhone). it took me about 3 seconds to produce this:



As you see, there is a resonant peak at 110 Hz, something at 180, a small one at 570 and a few other very small ones. These frequencies are indeed the 'tones' you hear when you tap the top of my guitar (they're different for every guitar). This is the 'thud' sound I referred to earlier, and this is the same 'thud' sound you hear after you pluck any string. Try it out yourself: plucking a string creates a sound as if you tap the top - after which the string will ring out.

However, as you can see from the graph, the resonant peaks are quite wide. This explains why you hear a 'thud' and not a clear tone, which would happen when you tap against a wine glass:



As you see, the spectrum of a wine glass has a much narrower peak, and therefore you hear a clear tone when you tap it, just like a church bell.

So yes, if a guitar body had similar resonance characteristics as a wine glass, then Andy Powers would have a point. Every time you would pluck a string, any string, the attack would produce a clear 'pinnnggggggg' tone, not a 'thud', which would probably be dissonant with the notes you played. But as we all know, the guitar will only produce a 'thud', with a wide spectrum, which lasts only very short, so it does not interfere with the intonation of the guitar, nor does it produce 'warbly' tones or 'fights'. It simply does not happen.

Another erroneous statement by Andy is: "...since guitar strings do not introduce pure sine wave signals, but multi-frequency content ... When you sum these things together, you end up with a surface that resembles wrinkling tin foil...".

I know where he is going to, but he is wrong. A vibrating guitar top does not look like wrinkling tin foil, but always vibrates in quite an orderly fashion, even for the high frequencies. Its behaviour is identical to the vibrational modes of a guitar string (albeit in 2 dimensions). A vibrating guitar strings contains a plethora of different frequencies, all happening at the same time at various wavelengths. However, the vibrating guitar string does not look like a wiggly chaos of all kind of different waves happening at the same time (the one-dimensional version of wrinkling tin foil): it essentially looks like a simple and orderly triangle all of the time. You can see this in the computer simulation I write a while ago:



it is true that the simple triangle contains many kinds of different frequencies, but they all add up to make a simple triangle. A guitar top does something similar, albeit in two dimensions.

However, the most disturbing point about Andy's story, in my opinion, is the fact that he only tells that V-bracing solves all the alleged intonation issues, but he never explains how it does such a thing. Why would V-bracing systematically shift all resonance frequencies towards positions where they are "more in tune" with the strings? How can you reproduce this effect on mass-produced factory guitars? If it works so reliably, there must be a very fundamental principle underneath it. But Andy fails to make this clear - in fact he does not even mention it. I think that is disturbing.
First of all, I am not an audio engineer, but what you are saying makes sense. I also want to download one of those apps to try out with my guitar. Thanks for including the graph images and going to all that trouble in your post. I appreciated it!

That said, I still just go back to Taylor biting off more they can chew with their marketing. All they had to say was, "We developed a new bracing pattern. We like it, and we think you will too..."
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  #57  
Old 03-08-2018, 09:28 AM
Picker2 Picker2 is offline
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Originally Posted by Shades of Blue View Post
First of all, I am not an audio engineer, but what you are saying makes sense. I also want to download one of those apps to try out with my guitar. Thanks for including the graph images and going to all that trouble in your post. I appreciated it!
It was entirely my pleasure, Shades of Blue.

Quote:
Originally Posted by Shades of Blue View Post
That said, I still just go back to Taylor biting off more they can chew with their marketing. All they had to say was, "We developed a new bracing pattern. We like it, and we think you will too..."
That's exactly what I wrote in my very first post here, and then hell broke loose...
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  #58  
Old 03-08-2018, 09:32 AM
jaymarsch jaymarsch is offline
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Thanks, Herb, for asking for an explanation and posting the response here. Since I am not a builder or a sound engineer, I am not in a position to debate the assumptions and assertions but as a player, I have played guitars that exhibit issues with unpleasant harmonic content and those that don’t. If the V class bracing offers another solution to dealing with those issues all to the better.
I imagine some folks will hear the difference when they play the instruments and others won’t notice much of a difference.

As an aside- not meaning to hijack the thread, much of the discussion about the V-class bracing and the claim that it will render X-braced guitars obsolete reminds me of the outrage that ensued in the early ‘70s when a computer programmer created an algorithm (I think that is the right term but correct me if I am wrong) that had the computer spit out every haiku poem that was mathematically possible to be written. The literary and artistic community went ballistic. They felt that something sacred about the artistic process had been exploited and violated.

All this to say that after 6 months or so, it all died down. People still create haiku poetry and people are still moved when they read a poem that touches them. Nobody seems to even know or care that the poem was written by a computer forty some odd years ago.

Folks are still going to make music on X-braced guitars, V-braced guitars and cigar box guitars. And people will still be moved by the music that touches them.

Best,
Jayne
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  #59  
Old 03-08-2018, 09:37 AM
Shades of Blue Shades of Blue is offline
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That's exactly what I wrote in my very first post here, and then hell broke loose...
Been there, done that!

Another issue I have is that Taylor is all set to roll out the new bracing pattern by the end of 2018. Why do that without some real world market feedback on your product? Why rush to implement? Let the market tell you what it wants and then go from there.
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  #60  
Old 03-08-2018, 09:47 AM
TAYLORFAN50 TAYLORFAN50 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.
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