Paul H. Jacobson, Luthier

Custom Hand-crafted Guitars

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  • Question—I was looking for information about Intonation. I'm an amateur classical guitarist and have a [maker name withheld] classic guitar. Being a bit handy, I made a saddle to lower the action. I like it very low, the lowest possible without fret string buzzing. Your article about intonation was very informative. Wish I knew about you before buying my guitar. Question, would a lower saddle change intonation from a higher saddle? I've lost the original saddle to make a comparison. I am more aware now that the Et, B & G strings get flatter going up the finger board--especially the Et. Right now I compensate by tuning these open strings a bit sharp to be in tune higher up, but it's driving me crazy!!! I shouldn't have to do this to such a nice guitar. The D, A and Eb are perfect. Would love to hear you before I try to make a new saddle that would shorten the treble string distances.Dennis M. Rief, Miller Place, NY.

    Answer>...would a lower saddle change intonation from a higher
    saddle?<  It could, but it would take quite a bit of saddle lowering (say, 1/16" or more) to make the change audible if the intonation is accurate to begin with.  However, if intonation on any of the strings is already flat higher up on the fingerboard, lowering the saddle just a little will increase the flatness...and make it more noticeable.
    Everything you tell me indicates that the saddle on your guitar is OVERcompensated, i.e. too much setback.  (This is unusual: typically compensation is too little.)   I also suspect from what you say that the compensation is uniform, or nearly so, for all strings; I'd be surprised to find out that there is a treble-bass back slant in the saddle slot.  If the saddle break points for the flat strings are substantially back from the front of the saddle, it may be possible to make a new saddle with break points set forward to create the correct nut-saddle distance specified in my intonation article.  However, if the flat-string break points are at or very near the front of the saddle (and I'd be surprised if they weren't), it would be necessary to fill and re-cut the saddle slot (assuming there is enough wood on the forward side of the saddle block for this) to create room for correct compensation.
  • QuestionIf the sound board is the "speaker" why cut a hole in it?  Just tradition?  Ease of access to the braces for repair?  If it is so hard to brace around the intrinsic weakness of the "sound hole" which I understand should more accurately be called an "air port", why not put the hole somewhere else, a la [Linda] Manzer guitars' side port?Marc Durso

    Answer
    The "speaker" metaphor is sometimes used in describing soundboard function, Marc, but it isn't apt: the soundboard doesn't work that way.  Instead the soundboard conveys sound waves to the body cavity which are modified by the back as resonator.  The soundhole constricts and focuses the resulting sound waves as they emerge, and this is crucial for the the actual tone outcome.  If there were no soundhole, you'd get next to nothing in the way of tone, because the soundboard surface alone would scatter the sound waves.  Alternative sound holes (e.g. Manzer's side port) are valid alternatives.  Such options have to be judged on the actual tone outcomes they produce.  Actually it's not particularly difficult to brace around a soundhole I use a rather large soundhole pad which seems to work quite well.
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