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I'm drawing another guitar and I ended up with an X brace less than 90 deg,actually it's 85 deg. I've wondered about the placement of the x brace numerous times in the past. I've read where some folks have 92,90, and son on, but, I haven't seen any under 90 deg. Does an x brace under 90 deg. have a tendency to be deeper or higher in pitch? Will an x brace under 90 deg have less structure integrity? Clinton

As you narrow the x angle you will bring out more of the mids and trebles. It is absolutely critical though that your bridge spans the legs of the x-brace. I would make this your #1 concern and the angle of the x secondary (but still an important consideration).

I have a couple of my guitars that use 87 degrees.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

If two angle segments of the X brace are under 90* the the other two have to be over 90* right

Anyway many guitars are built with X braces where the angel in line with the center line of the body is less than 90*. To me the important issue is "Does the X-brace properly support the wings of the bridge?" If so then the rest is nuances that will affect tone in some way or an other. but it is the whole of the tops bracing in conjunction with many other things the determines the tone. Providing the structural integrity of the top does not require a 90* plus angle in its self.MichaelP39080.7212268518

How close to the soundhole is the intersection? Can you move it closer and open up the X?

Mine are generally about 32mm (1 1/4") from the soundhole (100mm Diam) and come out at 92 degrees. But, as Brock says, the most important thing is to have the wings of the bridge well supported.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Yes, I made sure the brace intersected the bridge wings. Now @ 88 deg the brace is 3/4" from the tangent of the soundhole,7/8" from the upper transverse brace. At 85 deg it runs 1/2" from the tangent of the soundole and a 1/4" from the upper transverse brace. ( I like that one better) The bottom of the SH to the crotch of the x brace is a whopping 1 3/4". Maybe I should lower the SH closer to the crotch and go with the 85 deg. I should mention this a 13 fret and lowering the SH would mean I should go with 20 frets instead of 19 to cover the top of the sound hole. If narrowing the angle means bringing up the mids and trebles I don't want to do that because it's close to a L-00 size. But maybe the 13 fret design would counter that. Clinton

When you say the X braces need to support the bridge, I am bit confused.
As the X braces span out and cross over the headstock side of the bridge,
can they exit out the sides of the bridge or should they exit out the back
(tailblock) side of the bridge?
Make sense.

I have had mine so they exit out the side of the bridge at the back corner
towards the tailblock.

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Andy Z.
http://www.lazydogguitars.com

Ask Dave White this question and He'll tell you what he uses. Every picture I've seen of his shows his x-brace angle below 90*

I stole this off your site Dave, hope that's ok

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[QUOTE=Rod True] Ask Dave White this question and He'll tell you what he uses. Every picture I've seen of his shows his x-brace angle below 90*

I stole this off your site Dave, hope that's ok

[/QUOTE]

No problem Rod.

I use an angle of about 75-78°. I have my top in quite a big arch though (the braces are shaped to 13' radius) and so I figure I don't need as much lateral stifness from the X braces. It usually works out that the 1st and 6th strings on the saddle correspond pretty closely to where the X brace arms are. I settled on this design after looking at a lot of Stefan Sobell's guitars - a maker for whose work and sound I have enormous respect.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

[QUOTE=azimmer1] When you say the X braces need to support the bridge, I am bit confused.
As the X braces span out and cross over the headstock side of the bridge,
can they exit out the sides of the bridge or should they exit out the back
(tailblock) side of the bridge?
Make sense.

I have had mine so they exit out the side of the bridge at the back corner
towards the tailblock.[/QUOTE]

No, I don't really understand your question, but I think we are on the same page. All I meant was that your bridge needs to set firmly over the legs of the x brace.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Clinton,
This is the basically the same question I have in my 13 fret bracing thread. I think the answer is to move the soundhole down as Sylvan mentioned in my thread, and have a 21 fret board. I will have to move the X down too to get the X under the wings. Here is a pick I think explains what Andy is asking. Basically, how much of the bridge wing does the X brace have to cover? In this example(which is a lattice braced bouzouki) notice that the X comes out of the corner of the bridge wing. What if it came out more towards the soundhole leaving just a tiny bit of the bridge over the X?

Tracy

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Tracy
http://www.luthiersuppliers.com

Does it matter which way

azimmer139080.8897337963

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Andy Z.
http://www.lazydogguitars.com

I like my braces to kiss the lower corners of the bridge just the way Tracy's drawing shows it. Tightening up the X as in andy's lower drawing will help the trebles if you have a floppy top. This is a design parameter that can be tailored to each top if you wish. A very stiff top cross grain can be opened up even more if you wish.

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Jim Watts
http://jameswattsguitars.com

Thanks Jim, that is probably the best discription of what happens when I've herad.

Filed away.

Thanks

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Thanks guys. I'll check the top I'm using. It's only my third guitar,I'm not investing in AAAA tops yet so it might need help stiffening it up a bit. So pull the X together for high tones and spread them for lower tones. Cool. I'll check out Tracy's thread. Thanks, Clinton

Almost all of mine are designed to come out the side edge, closer to the front corner than Tracy has in his bracing drawing up higher in the thread. My X angle is 98 degrees on everything except baritones (90) and multiscales, which are completely assymetrical, and each one different depending on the scales and the straight fret placement. I use a trapezoidal bridge plae shape, and like Larrivee's have a transverse brace abotu 1/4 inch behind the back of that. On my 13 fretters (or anything new for that matter), the bracing layout is designed from scratch, depending on the scale, fret joint and soundhole size.

Here are the innards of a recently completed curly redwood topped 15.5 inch Siganture body. The bass side braces are cut short (the lower X and transverse that dont meet) to be let into the guitars armrest block. Because fo the softer redwood, I opted for wider fingers on this one, they are about 3/4 by 1/8 high spruce. I have also stopped using the big popsicle brace altogether, and now use the two neck block side braces as shown. The patch is EI rw, actually made from back cutoffs from the Larrivee factory !!! Local shop had a huge box of them one day, 20 for 5 bucks, I have about a ten year supply - nicely thicknessed and ready to trim up - beauty eh !!!

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

[QUOTE=Dave White]
I use an angle of about 75-78°. I have my top in quite a big arch though (the braces are shaped to 13' radius) and so I figure I don't need as much lateral stifness from the X braces. It usually works out that the 1st and 6th strings on the saddle correspond pretty closely to where the X brace arms are. I settled on this design after looking at a lot of Stefan Sobell's guitars - a maker for whose work and sound I have enormous respect.[/QUOTE]

Dave,

If I understand this correctly, your aim in employing the 75-78° X brace angel is to transfer more energy into the upper bout region. This coupled with the complete removal of the upper transverse brace, made possible by the inclusion of cantilever struts running from the neck block back to the waist, allows you to exploit more of the overall soundboard.

Now, Jim makes a point that this X brace configuration will potentially increase the mid and treble response. Now, with me being a firm believer that you do not get anything for nothing, the question for me is, and I mean no disrespect what so ever, does or did the bass response of your earlier guitars suffer as a result of the X angle? And, if so, what did you do to counteract that affect?

Great thread folks thanks for the input, we need much more on this topic

Cheers and Happy New Year

Kim

Kim,

Because I'm primarily a fingerstyle player, balance across the strings is something I've looked for right from the beginning of my building, and good strong mids and trebles are very important. As I said in my post, I think that the extra arching I put in my tops means that I don't need as much lateral stiffness from the X braces so there is already a sort of balance here. I also have a feeling (but can't prove it or provide the science) that having the outer two strings positioned on the X brace arms helps with the energy transfer from the strings into the top - braces are for energy transfer as well as structural stability. I also like the way I can link the upper bout arms of the X brace into the ends of the upper bout brace. I put this brace on last and it always amazes me how much the top really rings more when it goes on. A narrower X angle means less area of the top below the bridge in the angle of the X's, but more top area where the finger braces go - what does this mean . . . danged if I know!!

There are other things in my designs that contribute to the overall sound and balance - the soundhole is further towards the neck block than most other guitars and I use a wide soundhole (105-110mm diameter), I use tapered bracing and carve it to get the top ringing and sustaining clearly, I thin the top gradually behind the bridge to the tail block whch I think helps bass response as does a soundport in the upper bout side. Also using the carbon fibre buttress braces and free floating neck means maximum response from the soundboard.

All other things being equal, my low X brace angle and tapered bracing should make my guitars all mids and no bass/treble (is that the same as "All mouth and no trousers" ), but fortunately in guitar making things don't stay equal

I find it satisfying that these design principles give me the sound I want in guitars, guitar-bouzoukis/citterns and hollow neck lap-slide instruments. But if someone wanted a specific different sound I would be lost and have to learn all over again - this is why I am only a "competent" rather than "good" luthier. It's a good job that there are so many builders out there that a customer can get whatever sound the want.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

Thanks for the response Dave,

I have been very impressed by your work ever since visiting your site almost a year ago. Not that I am any real judge, but since then I have always thought that you are onto something.

To my minds eye, what you do seems to make good practical sense, not in the least gimmicky, but rather purposeful innovation as I see it.

Respect for your opinion is what attracted my question.

All the best Mate

Kim

larkim39082.4054398148

I'm glad we had this thread, lots of good theories and ideas out there. I lowered my sound hole toward the X brace and opened the X up alittle,to about 89 deg. I'm thinking that the small body will tend to have the highs and mids. Something I got from the Kinkaid book,he doesn't touch the sides of the X brace with his bridge patch, actually it's an 1/8" away. On my last one, I butted the bridge plate against the brace on the treble side and on the bass side I butted directly under the bridge and angled it away from the X about an 1/8". I don't know if that had a thing to do with the sound, but I sure like it. Clinton

Great thread folks, filed for when i make my own design, Thanks!