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  #31  
Old 07-16-2019, 10:56 PM
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Bruce Sexauer Bruce Sexauer is offline
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A vibrating guitar string is equally capable of transferring its energy at both ends. We mostly want it to do so primarily at the soundboard end. The neck has two main qualities that keep it from receiving the strings energy. One is rigidity, whereby it simply resists being excited by the string, and the other is mass, whereby it is simply too dense to be much affected by the strings relatively puny mass. A good piece of stable wood and an effective truss system can make a perfectly adequately rigid neck. Adding denser neck material, massive tuners, or the mass of the players arm holding the neck in a death grip are overkill if the necks rigidity has been handled properly.

IMO, of course.

Also, logic NEVER trumps science, it can only add to science. Semantics, of course.
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  #32  
Old 07-17-2019, 06:31 AM
ruby50 ruby50 is offline
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I was in college in the midwest in 1967 and one of our roommates in a big old house was an Indian fellow. He played an instrument known as a Veena. His sister played Sitar and performed at the Montreal World's Fair in the Indian pavilion, and afterwards, around CHristmas of '67, she spent a couple of days with us. The two played together twice - sort of a formal concert of traditional music.

Here is what I remember, although it was a long time ago. The Sitar was considered a feminine instrument, while the very similar Veena was masculine.

There are many types of each instrument, but this Sitar had a hollow neck and a gourd at either end, and the frets were mounted right on the neck. The sound was primarily designed to get into the neck and travel both ways and come out the gourds.

This Veena had a solid neck with a scalloped fretboard made of beeswax with the frets mounted on the top of each beeswax scallop. The sound was designed to travel down the strings to the single big gourd at the bottom. This is ultimate damping by a fretboard - nothing is going to get through it.

The two instruments sounded very similar and the musicians could trade instruments and play each easily, but the hollow necked Sitar was considerably louder.

Disclaimer - I may have the instruments mixed up, and even my date is in question, but that's my story and I'm sticking to it.

Ed
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  #33  
Old 07-17-2019, 09:04 AM
Knives&Guitars Knives&Guitars is offline
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Originally Posted by ruby50 View Post
I was in college in the midwest in 1967 and one of our roommates in a big old house was an Indian fellow. He played an instrument known as a Veena. His sister played Sitar and performed at the Montreal World's Fair in the Indian pavilion, and afterwards, around CHristmas of '67, she spent a couple of days with us. The two played together twice - sort of a formal concert of traditional music.

Here is what I remember, although it was a long time ago. The Sitar was considered a feminine instrument, while the very similar Veena was masculine.

There are many types of each instrument, but this Sitar had a hollow neck and a gourd at either end, and the frets were mounted right on the neck. The sound was primarily designed to get into the neck and travel both ways and come out the gourds.


This Veena had a solid neck with a scalloped fretboard made of beeswax with the frets mounted on the top of each beeswax scallop. The sound was designed to travel down the strings to the single big gourd at the bottom. This is ultimate damping by a fretboard - nothing is going to get through it.

The two instruments sounded very similar and the musicians could trade instruments and play each easily, but the hollow necked Sitar was considerably louder.

Disclaimer - I may have the instruments mixed up, and even my date is in question, but that's my story and I'm sticking to it.

Ed
Very Cool Story! I like it.
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  #34  
Old 07-17-2019, 12:29 PM
Alan Carruth Alan Carruth is offline
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"I have also heard you mention from previous discussions how as little as two Grams(about 30 grains?) can make a difference in the Top. I realize it is not exactly damping. But stiffness of a top might have a Type of Damping effect?"

As usual there are several things in play here.

Increasing stiffness and mass both add to the impedance of the system. Impedance is the ratio of force over velocity at a given frequency. Higher impedance means the thing is harder to move in general.

Adding stiffness without increasing mass raises the resonant frequencies. This alters the sound. Since it also increases the impedance, what you get is something that tends to be harder to move, and produces less sound over all, but the pitches where it's easier to move are higher, so the timbre becomes more 'treble balanced'.

A lot of what this 'sounds like' depends on the vagaries of hearing. One of these is that the senses are set up to detect changes. When you swap out bridge pins for some that are heavier, say plastic (3 grams) and bone (8 grams), the measurable differences in the response of the guitar are small. However, they can be relatively larger in the high frequency range between 2000-4000 Hz, where 'normal' hearing is most sensitive, and you're primed to pick up changes. The effects can be amplified when small changes in 'top' resonant pitches due to the change in mass and impedance at the bridge shift the pitches so that they line up more or less closely with other resonances of the back or the air inside. It's all something of a crap shoot, which is why it's impossible to predict what's going to happen with such a change, and why some folks hear big effects and others hear none.

Bruce Sexauer wrote:
"....I have had to wrestle with the possibility that I have no idea what I am doing. I have had to wrestle with the possibility that I have no idea what I am doing."

I wrestle with that one a lot as well.

In a sense this thread is a sort of 'Rectification of Names' . That was an argument in the philosophy of ancient China that held that everything had it's own 'proper' name. You could only understand things if you knew all of the names, so they spent a lot of time trying to find them out. This is the opposite of the philosophy of Humpty Dumpty ("Words mean exactly what I say they mean"), but neither extreme proved totally successful.
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  #35  
Old 07-17-2019, 02:20 PM
Knives&Guitars Knives&Guitars is offline
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Originally Posted by Alan Carruth View Post

However, they can be relatively larger in the high frequency range between 2000-4000 Hz, where 'normal' hearing is most sensitive,
Great information as always Alan. And you have done an excellent job at explaining all of this in a very clear manner. Explaining Science to the novice such as myself, is no easy task. You have done well at simplifying these theories.
I am especially fond of your notation mentioning that often the changes we notice, are largest in the 2000-4000hz range.
This is a basic concept of which many a Recording engineer will base their mixes from. They often target this range frequencies because of the fact that these are frequencies that stand out in a mix.
It is also possibly the reason why Less, is can often be considered more. Why Some people prefer mahogany over Rosewood. A common complaint among many AGFers is that Rosewood guitars become too complex with all of the overtones...thus the sound becomes confusing. Many engineers prefer a Mahogany guitars in a multi-instrument & vocal songs. It s helps in defining the guitar in the mix.
Many of my favorite recordings of melodic Rock music, was made with a jumbo maple. Maple's more limited range will sometimes make it stands out in the mix.
And I am currently using a Camel Bone saddle on my Rosewood guitar. I find that Camel bone has less harmonics. While I have not measured what frequencies Camel bone favors, I would suspect it also finds it way in the same frequency range mentioned.
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  #36  
Old 07-17-2019, 08:42 PM
Knives&Guitars Knives&Guitars is offline
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Originally Posted by Bruce Sexauer View Post
logic NEVER trumps science, it can only add to science. Semantics, of course.
Said with a smile and the greatest of respect:
"Never" is not in Knives&Guitars Vocabulary. There are so many feats that were once thought to be unattainable...But now are.
Time has a way of making fools out of all of us. Myself being at the top of the list.
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