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Quality/timbre of identical guitars

  1. Sep 3, 2014 #1
    Two identical guitars produce the same note with the same pitch. Will the quality of the note differ for the two guitars?

    I understand that the subsidiary waveform determines the quality of the sound, but since they are identical guitars, will the subsidiary waveforms differ?
  2. jcsd
  3. Sep 3, 2014 #2


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    Identical guitars, with identical strings, plucked in exactly the same way?

    Even two consecutive notes played on the same guitar with the same strings can sound quite different unless the player takes considerable effort to make the notes sound the same.
  4. Sep 4, 2014 #3
    They will not sound the same to anyone with any degree of training and/or ability. There are too many variables. "Identical" is extremely hard to come by in such a complex system.

    With organic materials such as wood, just because the back is, for example, even as specific as Brazilian Rosewood or Honduras Mahogany and the top Sitka Spruce, is no guarantee the grain (variations in size and density largely from seasonal growth but also includes anomalies from mineral concentrations such as commonly visible in Curly Maple, Birdseye Maple, Quilted Maple, Tiger-Stripe Maple , etc ad infinitum) is at all similar. These profoundly affect tone.

    If we step away from just "guitars" and go to simply "stringed instruments" we can approach a very instructive example in this matter. Stradivarius Violins sell for millions of dollars and for good reason - they have yet to be duplicated despite extreme (and expensive) attempts by craftsmen, history scholars, and scientists to do so. This "Holy Grail" has led to searching records for where the specific woods were grown, bought, stored and treated as well as finished, and also the application of some extremely expensive and capable scientific instruments.

    For example, deep Composition Analysis (at the molecular level) discovered that for whatever the original reason (sound? look? vanity?) precious gems were ground up and mixed in with the shellac. Attempting to duplicate these processes has so far failed to reproduce a Stradivarius.

    The opposite approach has been also tried - Spectrum Analysis of the sound and the creation of synthetic materials (which can be tightly controlled) along with specialized shapes have made very sweet sounding violins but fall very short of duplicating Stradivarius.

    Is this just Musician Mysticism with no measurable validity? I think not since I was trained by a 3rd generation Luthier from The Netherlands to restore fine violins. Although I'm afraid the most expensive I ever got to restore was an order of magnitude cheaper than a Stradivarius, I can most certainly hear the difference even within a workroom. In an actual performance hall, Washington DC's DAR Constitution Hall, with no microphones, for example, I experienced Isaac Stern playing a Stradivarius and was utterly astounded that this little wooden box was louder by far than the entire orchestra behind him, and the tone was so beautiful it made one want to laugh and weep at the same time.

    This brings to issue the final variable - the player. Isaac Stern was a true Master of his craft in that empirical sense of someone who studied and practiced and played until it became so-called "Muscle Memory", instinctive. To bring this aspect down off Mt Olympus, the difference in tone that comes from a guitar player's experience does not cease just by learning how to not make the stings buzz on the frets. Playing from sheet music also progresses from the "See the dog run. The dog can run fast" level to instantaneous fluidity, just as Math can look like hieroglyphs until a person has used it enough that it becomes language... a language that speaks to you upon sight.

    There are no identical instruments or players... just similarities.
  5. Sep 4, 2014 #4


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    Interestingly, blind tests don't support the claims that Stradivarius instruments are greatly superior to the best modern instruments.

  6. Sep 4, 2014 #5
    Thank you! The second link is to what seems a very thorough and objective test of a highly subjective quality. I've watched some documentaries and read a few articles about recent testing and each one has had some important gains. It may be that these gains have been to a whole that has improved some new violins considerably. As much as I revere the old Masters, I am glad that this has occurred for many reasons, not the least of which is the hope that someone besides a World Class Master can afford these instruments.

    That said, the fact does remain that particularly if constructed of wood, no two guitars are identical. However, they may be close enough to make a player (and his/her audience) happy and I suppose that is "where the rubber meets the road".

    The point I am making is that many systems are far more complex than they seem on the surface. A much simpler example than a 350+ year old instrument of wood, glue and finish is electric guitar pickups which, at first glance, are simply wire wrapped around a magnet. They have a Holy Grail as well which is the Patent Applied For Humbucking pickup from Gibson and strongly associated with Les Paul guitars between 1955 and 1959.

    Several companies tried to reproduce these revered transducers, yet they all sound quite different, from each other and from the original. When I was asked why I supposed this was so by a respected and successful designer/inventor of newer pickups, I replied the most logical answer was due to differences in "Q" caused by exposure to impacts and/or temperature as well as poorly controlled winding techniques. I further said the answer must be simple because just how much can there be to a magnet wrapped in wire.

    He responded that one can spend a lifetime studying magnets, or metal, or wire, etc etc. let alone their combinations,and really he was right even though showing him a meter he could buy to measure "Q" was very helpful in his own quality control. Things are rarely as simple as they may appear.
  7. Sep 4, 2014 #6


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    Unless one believes in magic, this is hardly surprising; most technical aspects of our lives have improved in the past few hundred years. It's strange when you think that the strings that were used in Stradivarius' time were very unlike the best strings that are used today - yet the Strads still sound extremely good. There just has to be a bit of the 'King's new Clothes' about this business - as with fine wines.

    Modern techniques are very clever - and very cost effective. Laminated backs are allowing leading makers to produce some excellent guitars at a fraction of the cost of their top models.

    I wonder when the prices of Strads will start to suffer. Quite some while, I expect.
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