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Hi all. I am making this question for all those who has knowledge on a comparizon in sound between these bracing patterns !
I know Its not like one can say exact this and that, but if you could make a wide comparizon I would be most greatful. I saw Rasmussens Lattice and got really interested ! what could I expect as to be different from a standard bracing pattern sj to a Lattice SJ to a double X. Lets pretend we got 3 tops "with exactly the same stiffness etc etc" braced as mentioned, then what could I expect to differ in tonality ??.

There are a few similar to this question on the archive, but nothing that goes into this on a depth. and by this I dont meen to get the answers in math. I also saw Josh bracings on the archive, and got lost totally in whats possible or not !!.

Lars.

I have not made a lattice braced guitar as yet, but I did do the standard vs double-X comparison a few years ago, using, by chance, an SJ platform.

I built the two guitars of Sitka spruce and maple. The tops were flitch matched, the backs were not, but they weren't much different in properties either. I matched everything as closely as possible while building. I took them to an ASIA Symposium and had about 60 people try them over the weekend, without telling them what the experiment was until after they'd played them.

The double-X braced guitar was slightly prefered by about 2/3 of the people who tried it. Some folks said it had more treble, and other said it had more bass. When I measured the output, it turned out to have a little more of both. Some players observed that the standard braced top had a more 'traditional' sound, while the double-X was more 'modern'. Al in all the differences were slight, but noticable.

The key to lattice bracing is that it reduces the unsupported span of the top between braces, which allows you to make the top thinner. Since most of the weight is in the top you can make a structure that has the requisite stiffness and lighter weight, so that it's eaiser to move. If a standard top itself weighs 120 grams, and the bracing weighs 40 grams, and you can reduce the thickness and weight of the top by half through adding 50% to the bracing, then you end up with 60+60=120 grams as opposed to 100+50=150. Most lattice tops reduce the thickness of the top by more than that. At some point I'll give that a try.

A lighter top with the same stiffness will tend to have higher resonant frequencies, and that should change the sound of the instrument. Whether that's good or bad is up to the listener to decide.

Al, I don't suppose you have any photos of the double X bracing you use(d) that you'd be willing to share here... ?

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Thanks Alan !
Right now I am tap-tuning the top until the tone sounds right and also feels right when flexing ! Now, Lets say I make a Lattice top, or double X, make the top thinner, then I can only imagine that as the top is that thin, the tap-tone will be gone or almost gone. So how then will I know when I am to thin, or to thick ?

Lars

That's not true. You can tap tune it the same way. Take notes on thickness and stiffness and tap tones so you know what to do next time. You'll want to shoot for a lower frequency tap tone than you are used to. Forget about scalloping and go parabolic.
I think you are going to like it! I do and the people that play my guitars do too.

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"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

Thanks Steve. You say make it thinner ! is a standard braced top is, depanding on the stiffness etc between .100 to let say .125 then around what would a lattice or dX be ?

Lars.

Lars,
I prepare my tops to a deflection value, not a thickness. I can't even guess without knowing what is the top wood, what size is the guitar, how stiff the wood is, what sound you are looking for and if it is a 6 or 12 string. About all I can say is that it is less than what you'd be comfortable with.
For example, if you would go .110" on a Lutz OM with your normal bracing, try between .090" and .095" and see how you like it. That's a pretty big difference. Be very careful with your bridge plate placement and size - you might want to make it larger than normal.

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"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

Steve, sorry for not writing a reply untiul now. Thanks for this info !! great to know. I am making 2 guitars, one of them will be a little experimental, so I will as you can understand by my posts make it lattice or doubleX or similar. it will be an SJ, 16" lower bout, my own body-design, but with inspiration from K.Ryans guitars. EIR B/S not sure on the top yet, choosing between "Alaska Bear claw sitka" and a German top. the germans Density is 422 kg/cubik, haven´t done a defl on it yet.
The top for the other guitar will be a german with a density of 326 kg/cubik meter !!, its light as a feather and very stiff.

Lars

I agree with Steve's comments. I have thinned them down to .060" and the top has had plenty of sustain throughout the voicing process. The guitars turn out pretty darn loud too.

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tim...
http://www.mcknightguitars.com

How do these work with a shallower body? Seems like they would be good for increasing the volume on a shallower body.