kencierp wrote: Are there a forums where guys and gals talk about redesigning pianos or saxophones?
I would guess there are forums where they tell how one is better than the other.
kencierp wrote: Just kidding -- it would be nice to be able to predict the "exact" characteristics of a guitar before we make one. It just seems to me the easiest way to do that is to copy one we've heard in person.
So how would you copy it? By copying the dimensions? By replicating the frequency of the first few vibration modes as close as possible? Copying the dimensions wouldn't necessarily work unless you were using wood with similar material properties (stiffness, etc.). So seems you could come closer to copying the sound of the guitar you want to replicate by trying to match the frequency of first few modes of vibration (monopole, cross dipole, and long dipole).
I will chime in here......
I have built a grand total of 4 dreadnaughts off the Antes plans, which I believe is pretty much standard, tried and true Martineste design, and I have to say that all 4 guitars sound remarkable. Now, none of you all have heard any of them, and you might not agree, but to those who have received and played them, they agree. I claim nothing here execpt that I followed a tried and true design, and it worked. I am aware that impovements can and will always be made, but hey, nothing works better for catching mice then the old reliable spring loaded mouse trap and a walnut.
All this to say, for me, I will continue to use the basic, known to work bracing patterns, hopefully learning to tweak them a bit to tailor the sound some, and be awesomely satisfied that I was able to even come close to making a guitar that sounds like a guitar.
However, I do enjoy listenting to you all so please do continue the conversation, it is quite stimulating.
Just my $.02, and thanks for listening. :>)
Well I just copy it -- within reason -- I go to Elderly's (where many fine guitars live), shadow the bracing, take measurements, use the same materials to construct the copy and bingo the end result is pretty close -- basic easy reverse engineering.
I just prefer to use a "real model" as opposed to a theoretical model.
If I planned to build a great piano I'd copy a Steinway, a great Saxophone I'd copy a Selmer. But that's just me.
Trevor’s clearly reference’s the work of others for his models. He also does not define the output of the model as definitive, rather as a tool to understand the characteristics of really just a handful of factors. Stiffness of the top, mass of the top, stiffness of the back and sides, sound hole size, volume and characteristics of the wood itself and its contribution as mass and stiffness.
The model he presents does not evaluate and cannot evaluate particular bracing patterns. It is only useful relative to a given guitar design and bracing pattern. If one wants to make minor alterations on a design to optimize for a particular sound characteristic, understanding his model helps. I do not believe he has any unique magic that is different than the understanding that a lot of experienced luthiers have. Rather he quantifies some of that knowledge into a model and uses the model to explain why it is true.
From what I could tell from what I have read, if Trevor wanted to make a guitar that sounded like a Martin D he would brace it just like a Martin D.
I've never built with a double X so I don't have any experience to share. It does look a little stout to me, especially out toward the perimeter. I taper my X down to about 1/8" where it goes into the kerfing, and the other braces taper to nothing an inch or so from the edges, and everything is scalloped in the middle as well. But I don't know really, there are an awful lot of old Gibsons out there with double Xs that people love -"
