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Concerning vibration sustain, wire mounted to wood base and metal base

  1. Dec 15, 2013 #1
    tonequester here. Greetings to ALL.

    I have posted about acoustic resonance on my last couple of posts, and have been given much good info. I have one more post concerning concerning this topic.. I am going to do an experiment to find out the answer to my query, IF there is no definitive scientific/physics related answer forthcoming. However, IF there is, it would save me the time and expense of the experiment.

    My query is this : If one were to mount 2 guitar strings of the same gauge, one rigidly mounted to a steel bar, and the other so mounted to a wooden bar, of the same dimensions, which one, if equally "plucked", would vibrate for the longest period of time ? I would of course mount both strings above each bar the same distance, perhaps 1/4 inch, and would have to devise a method for equally plucking or striking the string, as well as placing both strings under equal tension. Also, would it matter if the string were single stranded, or wound, as guitar strings are of both types(don't think it would matter).

    I believe that an answer to this question will satisfy, what I have been trying to determine all along, but was not insightful enough to realize before, exactly how to post. I also pledge that my next post will not concern acoustics !

    Any and all comments are always welcome, but surely there is a simple answer, based on the Laws of Physics, that will encompass my curiosity. Thanks in advance....tonequester.
  2. jcsd
  3. Dec 15, 2013 #2


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    The devil is in the detail here, I think. You are presumably suggesting a fret and bridge at the ends of each and a massive bar in each case. There would almost certainly be energy loss in the mounting of the fret and bridge and I am pretty sure the loss in the wood would be a bit higher. But the two systems would have very little internal loss that I would imagine that acoustic sound radiation from the strings and air turbulence plus friction in the strings themselves would start to become significant loss mechanisms compared with losses in the bar and mounting.

    The 'Hawian style' guitars could be made this way (massive thick neck) because you don't put your hand round a neck. That may be in order to get good, natural ('passive') sustain. The slide will be less lossy than a finger behind a fret, too.
  4. Dec 15, 2013 #3


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    Absolutely. If you took your "metal" design and put a spot of grease or oil under the contact points of the string with the bridges etc, the results would probably be very different (This is a well known "trick" played on people learning how to do vibration test measurements, and it teaches then not to ignore step one of the procedure - make sure everything is clean and dry!).

    That's one reason why guitars sound better with new strings - new strings are cleaner than old ones.
  5. Dec 15, 2013 #4
    Greetings sophiecentaur.

    I don't mean to "pick on" you exclusively here, but am very happy that you replied. If I am understanding you correctly, it sounds like my "gut intuition" about this is correct. I don't know about loss from nut and bridge in this case, as I was going to make nut and bridge the same construction on both wood and steel "bodies". There must be some loss at nut and bridge in any design, I would think. I mainly wanted to narrow this down to the bodies effects on sustain of string vibration.

    There are two basic camps concerning mass of body and neck. One camp(mine) maintains that added mass increases sustain, while the other camp maintains that the more resonant the wood body and neck are, the more sustain one gets. All one has to do to see that added mass delivers sustain, is to CAREFULLY clamp a pair of Vice Grip pliers onto a headstock and hit the strings. For a short time, there was a product for sale called a Fat Head. It was simply a fairly hefty piece of brass that was cut out to fit, and be installed on the back of the head stock.

    The "tone wood" peoples(sellers of, and buyers of) propaganda made it unsuccessful. It's not that I don't think that certain woods don't impart a characteristic tone, although I believe that even than. it's made too much of. It is just that since playing a heavy Les Paul, and noting better sustain(without amplification) than any Strat I've ever played, I figured early on that mass must equal sustain. I now realize that it's more complex than that simple statement offers, but I do believe this. On SOLID BODY guitars, one should worry about a particular wood more for it's beauty, seen through a clear finish, than to pay big bucks for a wood because it is supposed to affect tone. In other words, wood's influence on tone is but a tiny fraction of what electronic design can accomplish, even if one only uses passive technology.

    Now, on an acoustic, by all means do your home work, and pop for the best wood that suits your chosen tone. Other than construction design, and perhaps finish applied, there isn't much more one can do that will influence tone. There is a big mark up of "tone wood" prices in the guitar market/after market. As a long time wood worker who has turned many an exotic wood bowl, turn tables, and finials on the lathe, besides being a carpenter, I know wood. However, acoustic possibilities are not taught nor learned by traditional woodworking. You better bet that I know prices though.

    Thanks once again for your very welcome input on this forum. I can only hope to "return the favor" someday !
    Best Regards, tonequester.


    If you ever decide to go further with that electric, and your blues tone, "than man has ever gone before", just give me a hollar !
  6. Dec 15, 2013 #5
    AlephZero. greetings, and thanks.

    I never really thought about the "lube trick", and I always lube(silicons) strings, nut, and bridge saddles at string changes, sometimes in between. I also have to agree with the thought about clean strings, or clean surfaces needed for the experiment. I once was given a "trick" to try with old strings. I was told to boil the strings in water for a couple of minutes, and then wipe them down with alcohol and dry. When I did this, the re-installed strings DID sound brighter, noticeably. It's just too big a pain to do regularly. Grit under strings at nut slot and bridge saddles could be the very reason the strings break at those points when they do. I always clean out the nut slots with a tooth brush before lube is applied, and the same with saddles. However, I would have given no thought to this "clean approach" with the experiment, which I may just do for the heck of it.

    Thanks again for your reply and info. Best Regards, tonequester.
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