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Nothing really experimental here, as I mostly busy myself thinking "inside the box". I would consider my work traditional in any case. On the last few builds I replaced the finger braces with finger patches, and I like what I hear and the control it gives me. I also mortise the soundhole braces under the UTB, and use a soundhole doubler for added rigidity in that area, and have always done so.
Back braces are capped on large(r) guitar (anything bigger than an 0), and I add a side doubler on huge guitar (bigger than a 00). Rick Turner needs to be credited for the last two features.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

On my first guitar several years ago, and now on my current build I used an X brace for the upper bout. The braces tuck partly under the headblock and the other ends have dowel pins at the butt joints with the main X brace.


I don't have the experience or enough history with this to make any claims. However, the first guitar, which has a too thin cedar top with cedar bracing no less, has survived some pretty severe humidity extremes through summers and winters, and the upper bout looks good. (the lower bout not as well)
Gerry

Ok Haans here you go.

Soundboard is about 3mm upper bout - 2.25 lower (ish!). 11-52 strings, 12th fretter.
The Ash was super hard almost waxy !? Really nice stuff. Thankfully its belly hasn't appeared yet, the areas pulled up but nice and uniformly. No weirdness when you look at the top under a light. .
Heres some pics.

Bob C, must be a lot of stress on those Weissenborns, high action and all?
Ken, very interesting pattern! Hard to tell from the angle, but looks like a little ladder influence there, yes?
Yes, , green is good, but look out for orange and red. Be very afraid...
Laurent, I don't like to mess with the outside much either, but inside is where I do my work. I have tried the soundhole doubler and like the idea, but lately have gone back to lamintated bracing for the SH. I've also done a brace with a wide spruce strip next to it about .1" thick and 1/2" wide. I've thought of that hardwood brace cap many times, but as of yet haven't gone there.
Nice work Jerry! Lots of side braces there.
Jonsse, that is a lovely instrument! Wonder if it sounds anything like white oak? What kind of top is that?
I got the back on my MJ last nite, and the tap is big, and hollow log thunk. I think I will put a new top on it though as I think I should go a little tighter and even thicker on the top. Might just be a little mushy sounding in the tap. It's really got the ladder sound though! Pretty pleased with where it seems to be going.

As a newbie, EVERYTHING is experimental to me. Not really much of a conformist either so my stuff might be pretty interesting in a year or so. Love the innovation in this thread.

Ian, it's good not to stray too far on your first builds, but when you have a good feel for building them and have some idea of what to expect, you can start making some innovative changes. Best to kinda go one change at a time so that you can get some idea of what the difference was tonally.
Then of course, there is the totally intuitive approach, but that is more hit or miss, AND, you might find yourself doing things like replacing tops before you get the binding on. Better doing that though than finishing the instrument and finding yourself with a dog.

I suppose my ascent series belongs here. This copied from my website:

I am pleased to introduce the new Ascent guitar series. These guitars encompass a number of ideas that I have formulated over the past several years. The main concept is to effectively couple the strings to a flat top guitar with significantly reduced stress on the soundboard. This allows the soundboard to vibrate more freely and accommodates a great deal of freedom in shaping the sound profile of the guitar to suit the player's needs.

This is accomplished using a special bridge/saddle system designed by Ned Steinberger and Steve Grimes along with a tailpiece. The tailpiece I chose to use for these guitars was designed by Erich Solomon. The key important element in my approach is that I incorporate an appropriate break angle in the strings to apply the optimal amount of force to the soundboard, effectively coupling the strings with the soundboard. In contrast, zero force was exerted by the strings on the soundboard in the design originally developed by Ned and Steve.

Please note, this design is very different than the old tailpiece Stella guitars, as well as traditional gypsy jazz guitars. The force experienced by the soundboard is much less than with those designs, allowing for a fuller, richer, and more resonant sound.

The result is a highly dynamic and responsive guitar. The tonal character can be varied greatly with the choice of bracing patterns, wood species, and variations in soundboard thickness. All this can be accomplished with absolute long term structural integrity.

A couple of bonus features of this design are the exceptionally broad color range that can be achieved when playing up and down the strings and the significantly reduced feel in tension experienced when fretting.

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Randy Muth
RS Muth Guitars Website
RS Muth Guitars Blog
Facebook Fan Page

VERY nice Randy!
One of these days I will get to a tailpiece guitar. I did a lot of experimenting with break angles on mandolins and as you suggested, sometimes less is more. It seems a more practical approach to guitar building than stuffing the ends of the strings into the top. Definitely going to put that on the list!
I am onto a 2nd top with ladder-X bracing, and will build a second guitar along with my first. I've made the top thicker, and cut the bridge patch from a thick piece of spruce stock that is first radiused to the top arch. Top is also thicker yet, in the upper .130's at this point.

Thanks Hanns.

I only have a 4 degree break angle over the saddle using the Grimes/Steinberger bridge concept. This only puts about 10 pounds of force on the top, so I can make it very light. The soundboard on the first guitar I made using this concept was thicknessed and braced like a classical. I could have done a standard classical bridge with nylon strings and it would have sang.

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Randy Muth
RS Muth Guitars Website
RS Muth Guitars Blog
Facebook Fan Page

Randy, that looks really attractive. Is it similar to the design used on the Spanish laud where the bridge/saddle is really low? Do you experience any sympathetic resonances behind the bridge with the length and low angle?

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Laurent, I don't know what the break angle on the Spanish laud is, but without the special bridge/saddle system it would have to be significantly greater than what I'm doing. Otherwise the strings would just buzz on the saddle. The break angle necessary to avoid that is incorporated into my saddle horizontally, although there are other ways to implement the Grimes/Steinberger system. Behind the bridge the strings are no different than they would be with an archtop or gypsy jazz guitar, albeit mine are longer. I should mention that this is the same tailpiece that Erich Solomon uses on some of his guitars. He graciously let me copy his idea for the tailpiece. I haven't noticed any problems with sympathetic vibrations, but you could put dampeners on the strings behind the bridge like some do with archtops.

This system frees me up to do what I want with the top although for tonal reasons there should be a balance between the amount of downward force and the stiffness/weight of the top, but I don't have to worry about torque. I determined that about 10-12 pounds of downward pressure puts my build (stiffness/weight) in the ballpark of a traditional flattop guitar, but I can move freely in that ballpark without having to worry about structural constraints.

As mentioned in my previous post, the first guitar I built using this system was built as a classical. But with steel strings driving it, it was like a classical on steroids along with the high frequency energy that's hard to get from nylon strings. When holding the guitar and speaking in a normal conversational voice, the guitar vibrates in your hands like crazy. It was incredibly responsive, but as one would expect at the sacrifice of sustain. That one sold at Woodstock to someone who was looking for that. The next one I built, I moved everything in the direction of a more standard steel string in terms of weight and stiffness. That's the one shown in my previous post. I have a lot of exploring to do with this system. Fun, fun, fun.

Here is a quick diagram to hopefully illustrate what I mean about the saddle.

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Randy Muth
RS Muth Guitars Website
RS Muth Guitars Blog
Facebook Fan Page

Awesome build, Randy! I've heard of the zero-downforce bridge, but I think that one's patented, so this is a good alternative for the rest of us to play with low downforce instruments.

And coincidentally, this lead to an "aha" moment for me
I just happened to be browsing around Michael Greenfield's site, because his guitars are amazing, and was looking at his harp guitars. What do I see? A bridge exactly like this on the sub-bass strings, yet a normal pin bridge on the standard strings. I'd seen it before, but never made the connection that it was to reduce the bracing needed to support the heavy sub-bass strings. Brilliant. Brace like a moderate/heavy 6-string, and compared to the mass and tension of the sub-basses (which can go higher than normal since they have no frets), that would be very light, perfect for the low-downforce bridge. And beyond that, you can tune the large back and air mass of the harp guitar to help pump some sustain into those low notes, while leaving the not-ultra-light top to support the mid to high notes sufficiently on its own.

I hope Michael doesn't mind if I rip off the concept.

One more bracing style to try on the retop test guitar That is, as long as it's ok with you that I borrow the concept as well.

Are you using longitudinal carbon tubes (a'la Haans ) or any other reinforcement with this bracing style? Seems like a good idea, since the top is so light, and still has the strings trying to crunch it length-wise. I love the violin style, where the downforce of the bridge on the arched top is what counters the length-wise crunch of the strings. But with low-downforce, and a flat face, I think the reinforcement bars underneath would be in order.

Dennis, a couple of things.

The patent on the bridge, now held by Ned Steinberger, covers the concept of zero torque. So the bridge on my guitars is covered by his patent. That is why I have his explicit permission to use it.

The idea to explore the range between zero downward force and the amount of downward force necessary to define the endpoint of the string on a traditional tailpiece guitar is my own as far as I know. I have no intention of patenting it, but I am a professional builder and I'm currently marketing this concept as part of my business. I would just like that to be considered.

The bracing pattern I've developed is also uniquely mine and has been years in the making. There's a lot more going on than can be easily seen in the picture and it was developed with respect to what I am trying to achieve with respect to the main resonance frequencies of the top.

I just looked at a close-up picture of Mike Greenfield's bridge for the harp guitar and it is a standard floating type bridge. That is, the strings pass straight over the saddle, so nothing new there. And yes, Mike makes wonderful and beautiful guitars.

I am not using longitudinal carbon tubes, but I have a good amount of support to resist rotation of the head block as I do for all my guitars. I use a carbon fiber laminated upper face brace and an A-frame in the upper bout. The A-frame braces are let into the head block and are half-lap jointed (similar to the X-brace) as they pass through the upper face brace and continue on as soundhole braces. I also use a Spanish foot. If you look closely, all of this is visible in the bracing photo.

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Randy Muth
RS Muth Guitars Website
RS Muth Guitars Blog
Facebook Fan Page

Well dang... patents really irritate me. And this country's legal system terrifies me. Perhaps I'd best leave this can of worms unopened.


Of course I'm not trying to steal your customers, I'm only a newbie with an interest in developing new and alternative sounding instruments. Variety is the spice of life and all. I'm big on sharing of research and pushing technology forward for the good of all of us, so you can bet the results of my experiments will be posted here and elsewhere for all to benefit from.


No worries there, I wouldn't be copying bracing patterns, only the concept of a low-downforce bridge.


Indeed you are correct. Jumped to conclusions there. Maybe to a better conclusion than the real thing? Oh well, guess I'll stick with a pinned bridge for the sub-basses since I know that's safe.


Yeah, looks like plenty of support against neck torque. I was thinking more along the lines of compressing the whole thing lengthwise, and creating bubbles or dips in the top. But it does look like enough bracing there that it probably wouldn't be any more than the settling in on a normal guitar, and you would certainly know better than me looking at one photo. Still, never hurts to be thorough.

Patents irritate me too, but Ned is a really nice guy with a very rich history in guitar innovation. Believe me, in Ned's case patents are warranted. Here's a little history on him. http://thinkns.com/inside-ns/history.php

I have no problem sharing my ideas for others to use and will always contribute something when I feel I have something worthy to contribute. But if people chose to use them, I would just like consideration in regards to the time and effort I put into them and their value to me as a professional.

I did consider the overall compressive forces acting on the top, but I don't think it will be an issue. The fan bracing probably helps a bit in this regard. Of course most of the dips you see in the lower bout of a standard flat top are the result of the torque being exerted at the bridge. With my setup there is no torque, only a small amount (10 pounds) of downward pressure.

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Randy Muth
RS Muth Guitars Website
RS Muth Guitars Blog
Facebook Fan Page

[/quote] Yeah, looks like plenty of support against neck torque. I was thinking more along the lines of compressing the whole thing lengthwise, and creating bubbles or dips in the top. But it does look like enough bracing there that it probably wouldn't be any more than the settling in on a normal guitar, and you would certainly know better than me looking at one photo. Still, never hurts to be thorough.[/quote]

Bingo! by using the CF tubes front to back, you relieve the compressive force of the strings trying to pull the tailblock toward the neckblock and rotate IT. I found I could lighten mandolin tops that way. Bound to have an effect on tailpiece guitars too.

I don't understand how you could have zero force on the sound board.

This is all just by observation and logic, but here's my analysis... Take a guitar with a glued on bridge, and grab the bridge with your fingers. You can hold onto it without applying any force, or you can yank it up and down and side to side. So you engineer the guitar to where the strings have enough of a break angle at the bridge to unload their energy into it, but where it's sitting on the line between the two anchor points of the string so it's only contacting the string, not stretching it in any direction. Then it's just like your fingers holding onto the bridge without applying any force to it. The strings move the top by yanking the bridge in all directions. It will just give a different kind of motion than a torqued and/or downward pressing bridge. More akin to an oud/lute, I would guess. But since the strings are not anchored to the top as in those instruments, you can use higher tension strings and brace it more lightly.

I think Randy's idea of adding a little bit of downforce makes a lot of sense. It would be difficult to make a bridge that could actually be pulled in all directions by the strings. But with Randy's design, the saddle slots can accept side-to-side motion, downward motion is of course natural to just about any bridge type, and with 10lbs of downforce on the bridge, that allows the strings to move upward and achieve the same result as pulling the top with 10lbs of upward force.
One interesting point is that the angled saddle slots would actually apply a constant twisting force to the bridge, but since there are 3 pairs of opposing angles, they should mostly cancel eachother out... one method of keeping the break angle forces "inside" the bridge, not going into the soundboard.

I do wonder about the tone quality though... As I understand it, the torque of the standard guitar bridge or high downforce of a tailpiece bridge channels more of the string energy into in-and-out motion, perpendicular to the plane of the top, whereas an oud-style bridge puts a lot of effort into pushing and pulling in line with the strings... which unfortunately doesn't move air. The zero-force bridge is interesting though, because it's not favoring any direction of motion, so in theory you could brace the top to channel that motion any way you like. And since you can make the top so light, your energy budget is effectively that much larger.

...at least that's how I see it. Take with a grain of salt.

Here's a short scale 12 string top braced with the new ladder-X.

The large spruce bride plate is cross-grain to the top ? Any concern about cracks ?

-jd

Nope, don't worry about cracks. Cracks are a result of lack of humidity or WAY too much.
The large bridge patch is an inherent part of ladder bracing (see page one, Stella bracing). Can't speculate much on the how or why as frankly I don't know. Most likely, it transfers the vibrations in a different way to the top, and just looking at the thing, you can see that the vibrations are carried all the way across the top. Seems to me it frees up the top at the rear by not having the X there (something that's bothered me for years). If you want to get all Somogyi about it, would seem to me that it would make all three modes work better as the X is so rigid. However, I'm not too reduction oriented, so I'll just say this. I like ladders except for the tendency of the area in front of the bridge to sink. Having the X there helps, and the rest, we will just find out. The tap on the 6 is very encouraging, and I still have some work to do on the 12, but I think it's going in the right direction.
I like the idea that with ladder bracing, you can get away from too thin tops. To me the tone is always "in the wood", so the more wood you take away, the less tone you have. A friend of mine has an X braced guitar with a very thin top. He loves it because it has a wide dynamic range. I dislike it because to me it is loud, irritating and has no tone. In my mandolins, I always built them heavy and with thick tops. Everyone said my mandolins sounded "FAT". They took longer to break in, but they didn't sound thin and irritating.
As far as the upper bout Filipo, I add a block after the top is glued to the ribs. The brace is also maple.
As I said, we shall see...

Filippo, you'll remember that I use a rather hefty block at the top of the neck block that spans around 4" and is about an inch in depth by 1-3/8" (same as neck block), AND also holds the two CF tubes. Also the distance between the neck block and that maple brace is only about 3/4", and that it is a 14 fret, so there really isn't much room up there.
As far as too many, not enough bracing, don't forget that it has also to do with top thickness and size of the braces too...

Working on my Double top still...




Single Cut, Hollowbody, Neck-Thru Prototype




And a modded Rosewood Tele with Brazilian Board just for fun.

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Todd Lunneborg
http://www.tlguitars.com/
http://www.fretboardjournal.com/

Hey Todd, did ya'll forgot about the FB & bridge on that first one! Dang holes in the way.

Sorry, couldn't resist- how does that one work?

BTW, I really admire your work I've seen previously

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

[quote="tlguitars"]Working on my Double top still...


I've got a headache! Tell me that's the back Todd...