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"Bog wood" is wood that has been soaking for 5000-8000 years usually in a river, oak bog wood is hard to come by and very expensive, it is supposed to be denser and heavier than ordinary oak... Anybody give it a try under components?
v.i.
Million miles from home.
Follow Ups:
Gonna get some and cut it like the myrtle wood blocks and give it a try...
Will report back!
v.i.
Million miles from home.
but it is interesting and would be fascinated to try out. If the bog wood has mineralized, that is, partially petrified and absorbed the minerals from the water, it may behave more like stone, and may not be so desirable. If, as some scientists have theorized, where the cellulose walls have maintained their structure but the cores have been dissolved and thus can ring, it may be of some benefit. I suspect the wood has become mineralized,and thus the explanation for the increased density.
However, you ask a fascinating question that very few of us would be able to answer as the vast majority of us have no experience at all with the material, other than an occasional viewing of a TV show about it on the Discovery channel and some blurbs from my local art gallery. I wouldn't mind buying some scraps to play with.
I suspect it may serve well as a footer of some sort but you would have to experiment yourself and report back. I, for one, would be fascinated to hear of it should you try it. In fact I would be interested where you would be able to find the stuff. Last show I saw said they find in Australia buried in former swamp land. Something other than Oak may serve as better material though, but that is simply a wild guess with no factual basis at all.
Stu
There's that Russian company that put out the old Siberian wood platforms a couple of years ago. Their claim was similar: the density made a difference sonically.
As you suspect and testing results indicated, everything does make a difference, but in which direction (what freqs it's emphasizing or de-emphasizing) is the real question.
had a project where timber recovered from the Mississippi River bottom was made into flooring, I believe.
The trouble with hardwood of any sort is that it is resonant. Large blocks or slabs made of it will have strong resonant tones that are difficult to damp. Maple is highly resonant, and I wonder how much of the hype around maple slabs has to do with resonant contributions to the tonal balance.
I once spent a Saturday morning in a Woodcrafters store testing hardwood samples by rapping with my knuckle. What I got was a sore knuckle and the finding that ebony is the least resonant of the wood species present. Unfortunately, ebony is an endangered species and the pieces available were too small to make anything practical from them, as well as hideously expensive.
If the water-logged timber can be made into a stable lumber with less resonant properties, then it would be useful in audio supports.
At one point in time I was of the same thought: destroy all sources of resonance. However, the laws of thermodynamics preclude that: you can merely alter the resonant frequencies but you can not eliminate them (conservation of energy).
When we talk of removing resonance we are merely transposing it into a frequency which we hopefully believe is out of the audio bandwidth for the most part. That's fine for many applications but recently I have been experimenting in adding positive resonances. Considering that most of our conventional electronic components have chassis constructed of aluminum or steel, those metals must surely contribute to the sound of any component.
Over on Iso, I wrote up a little about my experimentation, selecting woods by their usage for acoustical musical instruments. Personally I like Spruce: a rather plain variety of pine. It rings and thumps quite melodiously but does does wonders for the midrange quality in any digital piece of gear. I believe we need to reassess the role of resonance and perhaps recognize that the addition of certain kinds may actually increase musical enjoyment. Of course, I do realize that this opens a bag of worms, in that it becomes a rather messy means of sound shaping, but it can be a useful tool to achieve better sound.
Food for thought, and of course YMMV...
Stu
Let me clarify this issue.
A solid object has resonant frequencies of vibration and has some amount of internal damping. If the damping is small, the object will ring and produce clear musical tones when struck. If the damping is large, no tones will result and the object will respond with a dull thud. "Small" and "large" relate to the degree of energy loss as motion is transmitted through the object. "Damping" is the conversion of the energy of motion into heat.
You are right that resonances cannot be eliminated. However, they can be damped enough to make them inconsequential. The challenge is to do this without adding so much mass that the fundamental resonances are shifted down instead of suppressed.
For example, many amps are made with thick aluminum face plates. These have no function except to impart a sense of 'quality' to an otherwise flimsy device. These plates ring like bells, and may affect the resolution of the amp circuitry. IME, it is difficult to damp them because they are so thick and strong. Adding massive damping material lowers and sharpens the resonant frequencies.
I believe hardwood used in audio has similar issues. Depending on the application, the wood object's musical responses may affect the performance of the audio circuit. Different species have different degrees of stiffness and internal energy loss. Thus my quest for an affordable, stiff, well-damped variety.
Of course, the frequency range also is important. If you are damping ultrasonic vibration (generated, say, by the piezoelectric responses of the ceramic bypass caps found in much digital gear) with wood objects that have their fundamental resonances in the audio range, then your spruce may be a good material to use.
I am wondering, however, if damping may not be exacerbating the issue. In using damping, most often we are using softer material to attempt to squash out those resonant peaks. The material will often convert that resonance into heat but there is a certain time lag in which it does this conversion. I wonder if a faster means of energy propagation may not serve audio better.
Case in point, I once found at a surplus joint a bunch of tuning forks tuned to low C, 126 Hz, in a package of some nice chassis's. I bought the lot and was playing with them and conveniently stuck them in the open end of my steel equipment racks, using the ends as a holder (being too lazy to bend down). To my surprise the system sounded better. Knowing that tuning forks will resonate at their tuned frequency if there is a similar resonant point, I did a little experimentation,. Surmising that the resonance was really 60 Hz the fundamental AC frequency I assumed that I was working with the first harmonic 120 Hz and I moved the hammers out slightly to lower the frequency of the forks, and the sound improved even further. Now improvement was heard even on a rack in which I had filled the tubing with sand and lead.
This led me into reconsidering the effects of resonance and how to best work with it.
Stu
I believe it would be practical to squash a specific resonance in an audio setup with a tuned counter-measure, such as is done with some skyscrapers in seismically-active areas. The concept of port-tuned bass reflex speaker enclosures is similar. Your tuning-fork experiment appears to be along these lines.
As I said earlier, damping is ineffective if adding mass with the damping material fails to quell the resonance, but simply shifts it to where it does more harm. However, if multiple resonances are present, it may be impractical to treat each one individually. Thus, the ideal of the optimally self-damped hardwood.
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