Recent discussion on this forum about humidity and how it effects flamenco guitars got me thinking about magnetism. Is it possible that a guitar made from wood with no ferrous components would respond to magnetic fields and changes. http://en.wikipedia.org/wiki/Diamagnetism

I find this an interesting study that wood actually repeals in the presence of magnetic fields. http://books.google.com/books?id=xBo6AQ ... od&f=false

I find it interesting that oak for example has a stronger diamagnetism than yew, maple, or sycamore. Oak is not considered a usable tonewood, but the other 3 mentioned are.

Diamagnetism effects are so weak that they wouldn't have any practical affect on a flamenco guitar under normal circumstances. The strength of wood diamagnetism depends on the strength of the ambient magnetic field the wood is in, which generally for an acoustic flamenco guitar is mainly the very weak magnetic field of the Earth. A guitar would have to be in an extremely strong magnetic field for diamagnetic effects to be strong enough to significantly change the acoustic qualities of a guitar.

-Bob

Sam, what're you slipping into your eggnog these days?

Maybe it isn't his eggnog. Maybe it is the secret ingredient in his Spanish tapa that he promised to fix for me! Regardless, there isn't any harm exploring extraordinary possibilities. Sometimes scientific fact is far stranger than fiction.

-Bob

David, Wish I could tolerate a good eggnog and add some fine brandy to it, but the vast reaches of my 41 year interest in string instrument making and tonewoods cannot be blamed on excessive indulgence in preparation for a fiesta. 9 years ago after vestibular nerve loss and inner ear damage, magnetism and micro-gravity, and how they effect the human brain nerves, became of interest to me as study of these factors helped me deal with a very serious disability. How does this all apply to wood? Since magnetism and gravity effect all things there is a connection, but it probably does not have any direct effect on how a flamenco guitar plays. Maybe it affects how the tree grew and a factor in why one wood makes better tonewood than others. Bob is right that the effect of diamagnetism in guitar woods is so weak it would not have a direct effect such as if one was playing an intrrument in a high magnetic field no changes would probably be detectable. The changes, if any, would more likely be in the player because of nerves affected by the high magnetic field. I found it interesting that wood has a diamagnetic property and it seems that the lower this property the better the tonewood, but the studies are too limited to make any claims.

Bob, No secret ingredient in my Oregon tapa with a Spanish flavor. Hot smoked paprika and olives are the main reason it has the Spanish flavor. Always wanted to take a guitar down to the Oregon Vortex and play it there, but my health won't allow that far of travel. Probably no difference in sound, but holding it traditional it might appear level. Here is an interesting thought ... many of the best tonewoods in Oregon come from this part of the state. World renown Lawton cypress or Port Orford Cedar comes from near this area as does much of the fine myrtle and madrone. http://www.oregonvortex.com/

SamC wrote:Always wanted to take a guitar down to the Oregon Vortex and play it there ...

I still remember going there as a small boy. It seemed like a very strange place and made quite an impression at that age. There must be a large iron ore deposit below ground, because magnetic compasses have significant directional pointing errors around there. There used to be, and probably still are, warnings about that on aeronautical charts.

We drove by there last summer, but didn't stop.

-Bob

Bob, It is a fascinating place that has defied any theoretical consensus among the scientific community. The phenomenon is a visual one where one standing level and vertical can look like they are leaning to another a few feet away. I think there is a natural heavy magnetic field in the area that interferes with brain nerve function causing the inner ear nerves that send signals for balance to be out of phase with the nerves that send signals for visual thus creating this illusion. How does this all relate to flamenco? I don't know but I think it would be interesting to video a guitarist and a dancer from different angles and observe if the visual phenomena stayed in sync with the auditory. I also would like to go again since my inner ear nerve loss and see how things appeared in this area, since how things appear in "normal" areas changed after the inner ear damage. My eyes had to take over for the balance nerve loss on one side causing a bit of a delay on that side. I have trouble keeping my balance in the dark proving the connection of eyes and inner ear nerve loss. Several trees that grow in the southwest of Oregon have unique qualities that have been recognized by violin and some guitars makers for many years.

Since visual effects can be photographed and viewed other places they must not be due to local magnetic effects on brain nerve function.

Lucas

lucas wrote:Since visual effects can be photographed and viewed other places they must not be due to local magnetic effects on brain nerve function.

Lucas

That is a very good point and one reason the "vortex" has defied sound scientific explanation. A photograph shows exactly what one sees in person there. I think there is a lot about magnetism and micro gravity that scientist still cannot explain. It is a mystery how this illusion occurs and can be photographed on film or digital and shows exactly what one sees in person. It is like there is two dimensions.

It seems unlikely that local magnetic anomalies have any practical effect on flamenco guitars or sound they make, but it will be unknown whether they do until such time as practical effects may be found to exist or not. The main thrust of science is investigating and trying to understand unknowns and to those with strong interest in science both theoretical and practical investigation of any unknown is fascinating. Few if any questions are too preposterous to raise, because throughout history scientific findings have repeatedly seemed utterly absurd, ridiculous or contrary to common sense.

Lines on the map below show changes in magnetic declination around the earth between the years 1590 and 1990. If someone was located on a line labeled 20, for example, their magnetic compass would point 20 degrees east of True North or if on a line labeled -20, would point 20 degrees west of True North. Note that the magnetic declination in Spain changed more that 30 degrees over those years.


Aeronautical and marine pilots and navigators have to continually compensate for magnetic declination changes as their positions change around the globe. The changes are important enough and rapid enough over time that magnetic declination lines are updated twice per year on aeronautical charts (I don't know the marine chart update frequency). In addition to these relatively large-scale magnetic field variations around the earth there are many relatively-strong localized magnetic anomalies, such as in south-western Oregon. Special local magnetic anomaly warnings are printed on navigation charts in those areas so pilots and navigators can know that magnetic compass indications are not reliable.

-Bob