Wood debate, from a scientific point of view, with math.
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drewfx
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Some information that might be useful:
1. You simply cannot trust your ears. It does not matter that you think you are special and have good ears or not. Our brains preprocess what we "hear" before we have any conscious access to the raw data that arrives at our ears. Unfortunately this sometimes results in people "hearing" differences that aren't actually there - our brains sometimes put things there because it's expected that they should be there and we have absolutely no control over this. For this reason careful, double blind (or completely blind) listening tests are the only type of listening tests that are reliable as they isolate what we perceive from everything except what arrives at our ears. Sighted tests are of course much easier, but what they are useful for is making preferences between different things, not determining facts about the objective world. IOW if you don't do it right, you shouldn't pretend that you "know" anything about the world out there.
2. There has been a large amount of proper academic study of wood used in musical instruments using proper science, but understandably it tends to focus on classical acoustic instruments. IME you will get more trustworthy knowledge from violin luthier forums than guitar forums if you are interested in such things. Some violin builders have been known to do things like spend big bucks on devices that measure the speed of sound in a specific piece of wood so that they can put that info to use. If that sounds surprising, I would say that that's an indication of the difference between the approach to "science" of guitar builders vs. violin builders.
3. If you find a "scientific" discussion in which you don't already have expertise and don't find it at least somewhat confusing and filled with arcane terms and formulas then it probably isn't really a "scientific discussion" at all. Scientific discussions about wood will throw around things like Young's modulus as if everyone just knows what it is - I mean like, duh, Young's modulus. Here's an excerpt from what I would call a comparatively "friendly and easy to read" discussion:
http://www.amjbot.org/content/93/10/1439.full
Needless to say, attempting to acquire actual knowledge is sometimes much more difficult on us than we amateurs would like to believe. But the fact that the people who are really serious bother with such things should indicate that it isn't as trivial a subject as we might like.
1. You simply cannot trust your ears. It does not matter that you think you are special and have good ears or not. Our brains preprocess what we "hear" before we have any conscious access to the raw data that arrives at our ears. Unfortunately this sometimes results in people "hearing" differences that aren't actually there - our brains sometimes put things there because it's expected that they should be there and we have absolutely no control over this. For this reason careful, double blind (or completely blind) listening tests are the only type of listening tests that are reliable as they isolate what we perceive from everything except what arrives at our ears. Sighted tests are of course much easier, but what they are useful for is making preferences between different things, not determining facts about the objective world. IOW if you don't do it right, you shouldn't pretend that you "know" anything about the world out there.
2. There has been a large amount of proper academic study of wood used in musical instruments using proper science, but understandably it tends to focus on classical acoustic instruments. IME you will get more trustworthy knowledge from violin luthier forums than guitar forums if you are interested in such things. Some violin builders have been known to do things like spend big bucks on devices that measure the speed of sound in a specific piece of wood so that they can put that info to use. If that sounds surprising, I would say that that's an indication of the difference between the approach to "science" of guitar builders vs. violin builders.
3. If you find a "scientific" discussion in which you don't already have expertise and don't find it at least somewhat confusing and filled with arcane terms and formulas then it probably isn't really a "scientific discussion" at all. Scientific discussions about wood will throw around things like Young's modulus as if everyone just knows what it is - I mean like, duh, Young's modulus. Here's an excerpt from what I would call a comparatively "friendly and easy to read" discussion:
http://www.amjbot.org/content/93/10/1439.full
One feature that sets wood apart from most manmade materials is that it is an orthotropic material, meaning that it has unique and independent mechanical properties in the directions of three mutually perpendicular axes: longitudinal, radial, and tangential. The longitudinal axis (L) is defined as parallel to the fiber (grain), thus along the length of a tree trunk; the radial axis (R) is perpendicular to the growth rings; and the tangential axis (T) is perpendicular to the grain but tangent to the growth rings. This orthotropy is due to the cellular structure of wood. Wood is primarily composed of hollow, slender, spindle-like cells, that are arranged parallel to each other along the trunk of a tree. The microscopic properties of the individual cells such as their composition and structure, their physical and mechanical properties, and their shape and connectivity determine the overall performance of wood.
Wood is a hierarchically structured composite. The cell walls consist of cellulose microfibrils embedded in a lignin and hemicellulose matrix in which minor amounts (5–10%) of extraneous extractives (e.g., oils) are contained (Wood Handbook, 1999⇓; Dinwoodie, 2000⇓). Variations in the volume and chemistry of these ingredients, combined with differences in the amount and distribution of porosity, determine the structure and thus the density and mechanical properties of a wood. While the properties of a single wood species are constant within limits, the range of properties among species can be large. Worldwide, the density of wood ranges from about 100 kg/m3 for balsa (Ochroma pyramidale) to about 1400 kg/m3 for lignum vitae (Guaicum officinale) and snakewood (Brosimum guianense) (Wagenführ and Schreiber, 1989⇓), a value close to that of carbon-fiber-reinforced polymers (CFRP) (Fig. 1). However, even in Europe, which has a small diversity of tree species due to a relatively recent ice age, the density ranges from about 400 kg/m3 for willow (Salix alba) to about 800 kg/m3 for hornbeam (Carpinus betulus) and 950 kg/m3 for boxwood (Buxus sempervirens) (Sell, 1989⇓).
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Needless to say, attempting to acquire actual knowledge is sometimes much more difficult on us than we amateurs would like to believe. But the fact that the people who are really serious bother with such things should indicate that it isn't as trivial a subject as we might like.
amigarobbo
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Seems perfectly cromulment to me.
You don't build violin bows of out balsa.
I expect to see Young's modulus approximate value, on all 3 plains, for every wood offered by Warmoth, to be added shortly.
ccasion14:
You don't build violin bows of out balsa.
I expect to see Young's modulus approximate value, on all 3 plains, for every wood offered by Warmoth, to be added shortly.
ccasion14:
Strat Avenger
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I can definitely trust My ears. If there was a significant tonal difference, I would hear it. If I can't hear it, it's negligible and therefore a non-issue. That thin slab of rosewood or ebony (or whatever) is not enough to make a difference, and the pickups are not going to reproduce it. The body, and the core of the neck are substantial pieces of wood, and the strings are anchored between those two pieces of wood. That will make a difference. Of course the bridge and the pickups make the greatest contribution of all.
BigSteve22
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And it didn't get bleeped, not even in South Carolina! ???arealken said:
Cagey
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Street Avenger said:
I have to disagree here. The fact that they are "substantial" pieces of says that they won't make a difference. At least, the body won't. The neck is long and thin, and can vibrate more. Those clip-on tuners wouldn't work if it didn't. Since the neck is vibrating, that means it's absorbing energy from the strings. Depending on how much and at what frequencies, it will affect the what's left of the string vibration to be picked up by the pickups.
Speaking of which, some types of pickups are designed to be sensitive to mechanical vibrations. They usually take the form of piezoelectrical elements. There's less for them to pick up due to body mass holding things still, but they have little amplifiers to increase the signal from miniscule to small so the main instrument amplifier has something to work with.
That's why the experiment the original poster did returned results that say wood doesn't matter. He used pieces with a lotta mass and no neck. Basically just a body with strings on it.
So, body = little effect. Neck = some effect. Pickups/signal chain/amplifier = most effect.
drewfx
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For people who don't want to bother to read the proper science/physics stuff, here is a short summary:
Neck - there's a resonant frequency associated with the neck with the frequency based in part on the speed of sound (which is different for different woods). A dampened neck (reinforced or multi piece) will spread the resonance out over a wider range than a single piece of wood which has a deeper, narrower resonance. Graphite (carbon fiber) is at the extreme - i.e. flattest, most even response. Interestingly, one company (Moses graphite) manufactures graphite necks in such a way as to deliberately add some wood-like resonance.
So there may be something to the vintage guys who claim that one piece, more lightly reinforced vintage necks sound different.
Body - there is something called acoustic impedance and different materials have characteristic impedances. When 2 materials have similar impedances they transmit vibrations effectively; with very different impedances most of the energy is reflected back. To better couple 2 materials with different impedances you can put a material with intermediate impedance in between - if you've ever had an ultrasound, this is the purpose of the gel they use (aside from making you cold).
Think steel string acoustic guitar bridge: impedance goes high to low for effective transmission from string -> saddle -> bridge -> softtwood top -> air.
So on a solid body, some of the energy is reflected back to the string and some of the energy that it makes it to the body is stays in the body rather than going back to the string (or is absorbed by the body or transmitter to the air) relative to the different impedances of the strings/saddles/bridge/body wood. OTOH, acoustic guitars are designed to more effectively transmit vibration.
Neck - there's a resonant frequency associated with the neck with the frequency based in part on the speed of sound (which is different for different woods). A dampened neck (reinforced or multi piece) will spread the resonance out over a wider range than a single piece of wood which has a deeper, narrower resonance. Graphite (carbon fiber) is at the extreme - i.e. flattest, most even response. Interestingly, one company (Moses graphite) manufactures graphite necks in such a way as to deliberately add some wood-like resonance.
So there may be something to the vintage guys who claim that one piece, more lightly reinforced vintage necks sound different.
Body - there is something called acoustic impedance and different materials have characteristic impedances. When 2 materials have similar impedances they transmit vibrations effectively; with very different impedances most of the energy is reflected back. To better couple 2 materials with different impedances you can put a material with intermediate impedance in between - if you've ever had an ultrasound, this is the purpose of the gel they use (aside from making you cold).
Think steel string acoustic guitar bridge: impedance goes high to low for effective transmission from string -> saddle -> bridge -> softtwood top -> air.
So on a solid body, some of the energy is reflected back to the string and some of the energy that it makes it to the body is stays in the body rather than going back to the string (or is absorbed by the body or transmitter to the air) relative to the different impedances of the strings/saddles/bridge/body wood. OTOH, acoustic guitars are designed to more effectively transmit vibration.
Strat Avenger
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Well Kevin, I can here the difference between a hard ash body and an alder body of the same shape & size. The hard ash is much brighter (high frequencies). There is simply not enough material of a fretboard cap to make any difference in the tone of an electric guitar.Cagey said:
Cagey
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I'm saying the neck as a whole, not the fretboard. As far as the fretboard goes, I don't think it makes a great deal of difference, either. But I am with Aircap in that I think you can hear some difference in the attack. There seems to be a difference when doing hammers and taps. Otherwise, not so much.
As for the body, I'm not saying it makes no difference, only that it's minimal. If you can hear it, fine. If not, I'm not surprised. Usually when I can hear a difference, there are other things that are easier to attribute it to. Closest I've been to having two "identical" guitars to compare, they still weren't identical. Necks, bridges, pickups, strings, etc. all the same and they both had Swamp Ash bodies, but one was chambered while the other was not. Then I could hear a very slight difference, but only acoustically. Electrically, they were still very much the same.
As for the body, I'm not saying it makes no difference, only that it's minimal. If you can hear it, fine. If not, I'm not surprised. Usually when I can hear a difference, there are other things that are easier to attribute it to. Closest I've been to having two "identical" guitars to compare, they still weren't identical. Necks, bridges, pickups, strings, etc. all the same and they both had Swamp Ash bodies, but one was chambered while the other was not. Then I could hear a very slight difference, but only acoustically. Electrically, they were still very much the same.
