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One of the sweetest-sounding guitars I ever played was ladder braced, but I didn't have a mirror to look inside. Do you know if builders in that style usually put a brace directly under the bridge or only somewhere nearby? I know that Richard Schneider, in his Kasha-influenced instruments, put a transverse brace under the bridge, so it must be workable (um, of course, if one had his skill!). Thomas Humphrey uses a 90-degree lattice in his Millenium guitars, but I don't know if one of the transverse braces falls directly under the bridge. Any speculation/experience would be much appreciated.

Carlton

If you are talking steel stringed gutiars , I have a plan for a Gibson L-0 and refereing to that the ladder bracing has no brace other than a bridge plate under the bridge. There are transverse braces that are at the end of the fingerboard , below the soundhole and a tone bar that catches the trebel corner of the bridge
On the Classicals we have
Hauser
Kasha
Rameriz
Rodriguez
Fredrich
Martin
   I can tell you that some are braced under and some have bridge plates. None of the classicals on these prints used a ladder bracing but all use Fan or a variation of a fan stytle.
   John Hall
Blues Creek Guitars

Thanks, John

On classicals:

Friedrich has used a bar directly below the saddle at the front of the bridge footprint.

Bouchett has used a similar bar below the bridge but positioned more to the center of the bridge footprint.

Both were otherwise fan braced.

All this from the Roy Courtenall book "Building Master Guitars".

RCoates38563.0119791667

Thanks for the info, Ronn

Hey Carlton,

Earlier this month, I attended a lecture given by Dennis Cinelli, an expert on early guitars, including the rather wide variety that were being made during the Romantic period. Many of them, most notably those built by La Cote, were using a sparse ladder braced system. Sparse, in the sense that they had three, maybe four widely spaced "ladder" top braces, with one or two often at a slight angle off perpendicular from the centerline. These are gut-stringed guitars.

Dennis owns several of these instruments, and concertizes with them. He states that they are quite loud and robust sounding, and that the sonority is more raw and elemental than what one is accustomed to hearing from a more modern classical. Dennis said that one should look at a fan bracing system as being a sound "filter" -- that modern classicals have a more refined sound as a result. But he states that once one gets used to these older instruments, they are capable of great tonal ranges and color.

Looking at the slides he showed, I can't state with certainty that any of the ladder braces were placed exactly over the bridge saddle line, but I would not be surprised a bit if they were.

Now, as to the popularity and usefulness of placing a brace at the saddle, as Ronn mentioned, Bouchet developed a pattern with a cross brace under the bridge and had great success with it. He is probably the most noteworthy modern classical builder who has used one.

I developed an extended radial pattern, and borrowed an idea from Richard Schneider, which I incorporated into it. The heart of my bracing pattern is a cross brace directly under the saddle.



Note that the cross brace is asymmetrical -- it's a bit taller on the treble side. Bouchet did this same thing. As it turned out, this cross brace was way too big. I ended up shaving off about half its mass with a brace plane.

One of the points of this experiment was to see if the upper bout became acoustically active using the Schneideresque flying tone bars. (Most classicals with tone bars above and below the soundholes have upper bouts that are largely acoustically inactive) This worked. You can tap on the upper bout of the top of this guitar, and that of a traditionally braced classical, and hear the difference. This guitar's upper bout is noticeably more responsive.

Getting back to the cross brace though, one difference I note between this guitar and another I've built using this bracing system, when compared to other, more traditionally braced classicals, is these guitars have noticeably more sustain. I dunno if this is a characteristic of a Bouchet, but it wouldn't surprise me a bit if it were.

Best,

Michael

_________________
Live to Play, Play to Live

As usual there are two things to think about when bracing a top: structure and acoustics. As is also usual, in some ways they are fighting with each other, and you need to find some workable compromise.

The main structural problem is the torque of the bridge: top bellying and colapse is what usually kills guitars that survive all the other insults. If you think about the bridge as rotating around a line along it's bottom under the saddle then you'll see that a transverse brace at that location won't do much to resist that torque. You can easily stop a door from swinging in the breeze if you can put your hand on the knob, but try to hold it on the hinge side....

If you put the cross brace just in front of the bridge that will do a lot to keep the top from dipping there, and the closer the better (up toa point). Much the same can be said for a cross brace just behind the bridge to fight the bellying up. Most of the cross braced guitars I've seen have done it one of these two ways. The closer you put the brace to the bridge without actually running it undet the saddle the stiffer the top will be structurally, but the brace may need to be beefier due to the lack of leverage (see door example above).

The most structurally efficient way to keep the bridge from torquing the top is to run braces along the length of the guitar. Those seven little fan braces that Torres settled on probably don't weigh half as much as the single cross brace in some of the contemporary French or Viennese guitars.

Acoustically we've got a bit of a different problem: the top is a lot less stiff crosswise than it is lengthwise, and it gets to be more of a problem when you make the guitar wider to get more sound. It seems to be acousticaly desireable to convice the top that it is 'circular', in the sense that a wave starting from the middle of the bridge 'should' reach all of the edges (or the waist brace) at the same time. So you need to add some crosswise stiffness. Fanning out the braces under the bridge can do this, and you can change the angle to suit the crosswise stiffness of the wood. An X brace also works well. Where have we seen that...?

Another option is to use lengthwise braces to stiffen the top against bridge torque and crosswise ones to add stiffness for acoustical reasons. This has the advantage of allowing you to 'tune' the bracing to each individual piece of wood easilly and still use a single brace pattern.

Aside from stiffening the top in the crosswise direction the cross brace right under the saddle does two things as far as I can tell. One is that it adds to the impedance of the bridge. In the cases where I've used this sort of brace trimming it away doesn't seem to change the 'main top' resonant frequency much, so it's adding stiffness and mass about in proportion (if it's not too tall). By adding both it makes it harder to move the bridge, which helps define the string length more exactly (good) and forces you to use heavier strings and play harder than you would have done without it there (maybe bad). The dynamic range can go from ppp-ff to pp-fff when you add the brace: you get the same number of levels at a higher volume in exchange for more work.

The other thing that the undersaddle brace does is to 'pin' the node line of the top 'long dipole' mode. Although it's not as effective at moving air and producing sound, particularly in the low range, as the 'main top' resonance, this mode is important. One researcher noted that the major measureable difference he was able to find between 'good' and 'poor' guitars was in the level of the top long dipole mode. This resonance can couple with an air mode in the body to produce sound around A on the high E string, which fills in what would othewise be a 'hole' in the spectrum of the guitar. 'Pinning' the node line may or may not help this to work better: it's little hard to do experiments on just that aspect alone without changing other stuff. If it works for you....

I think we dismiss ladder bracing too easily sometimes, especially for lightly strung guitars. One of the nicest sounds I have ever heard came out of a ladder braced guitar as well. Built by an unknown maker in about 1780 this little 648mm scale guitar had a gorgeous lively even sound. As you can see its pin bridged but the bridge plate has the profile of a full brace at its front and tapers off to the rear.







Mind you, I think the 220 year old Euro spruce top might hava had something to do with its sound. I intend to build a copy one day so maybe I'll find out. Note also the angle brace below the soundhole, sort of like a proto semi X-brace!

This 1764 Brunner has an early set of fan braces (thought to have come in about 1750). It's fairly heavy ladder bracing was because it had 24 strings.





Colin

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

I have built several of the "Bouchet" style classicals and after a couple changed the brace for a patch. Now I'm trying something to Michael. It is a variation of an Adrian Lucas design. All the finger braces end inside the footprint of the bridge. I have shaved the main brace down from what you see in this photo to try to loosen the top up slightly. The guitar is in the process of being finished so I haven't strung it up yet and don't really know what is sounds like but when you thump the top is has a great presence. The Helmholtz resonance is G#. I'm not sure what that tells me. Any comments would be appreciated. Barry Dudley38564.4575578704

Michael...Thanks for the information. It's interesting to think that the "raw/elemental" sound described by Mr. Cinelli is probably what people thought of as THE "guitar" sound 2 1/2 centuries ago, and many might not have liked the more "refined" sound that we generally expect from the instrument today. You might like to search deeper into the Schneider/Kasha method, as I can say from experience that Richard's guitars have an impressive amount of sustain--so much so that it put off many players who tried them, because they'd have to adjust their technique to compensate for it.

Alan...Well, you've touched on several things about which I've been thinking, and more. Thanks for helping to clarify for me the effect of placing a brace to the fore, aft, or under the bridge, and the possible benefits of combining that with lengthwise braces, which is something I've planned to do.   Very useful information, as usual.

Colin...Those old guitars do have an attractive sound (and look), don't they? I've wondered, though, if it's just the bracing (or the aged wood) that provides the appealing sonics. There's something about those body proportions that just seem "right." That shape may have been wide-spread for reasons other than tradition. Also, those old masters eschewed putting a slab of hardwood on the soundboard, which, it seems to me, must have an affect on the sound. I'm guessing it was thought of and rejected by some luthiers before metal frets and player demand made it manditory.

Barry...Let us know how that interesting design sounds when it's completed. It's hard to tell without seeing it in three dimensions, but it looks like you could remove some wood from those fan braces, too, if it's for nylon strings, which I'm assuming. Take material from the brace sides if you want to retain stiffness, or from the brace height if the top is too stiff. I'm writing, of couse, more from what I've been told by knowledgeable luthiers, than from personal experience, so take it for what it's worth.

Thanks, all!

Back when I was sharing shop space with a friend we had a nice 20th century classical guitar come in for some work. When we looked inside we were astonished to find it was ladder braced. There was no clue on the outside at all; it looked like any other Torres-style box, and sounded like it, too.

When they had the 'Dangersous Curves' exhibit in Boston they placed the Pages and Strad guitars in such a way that if you stood back you could catch them both in one view. Two instruments built more than a hundred years apart, iirc, and the outlines were about as similar as, say, a Martin and a Gibson Dread. There's got to be some reason.

I used that information to build a little 'Renaissence' guitar (with six courses; not 'authetic' but what the customer wanted) and (of course) ladder bracing based on the Strad. The sound was just right for the music of that time: not as 'silvery' as a lute, as you might expect, but perfectly suited.

Each design and brace system has it's own characteristic sound. We use what we use because that's the easiest way to get the tone that people seem to want now, but it's not the only way. I wish I had some acoustic measurements on that one we worked on years ago.

Alan,

Years ago I wondered why lutes and guitars, given similar bracing styles, woods, and strings, sound so distinctively different from each other. My first thought (befitting a novice) was the bowl-shaped body of the lute. Later, I realized it's largely a result of the narrow waist of the guitar. Sure, it was probably influenced by the viol-family shape, but it was still a superb innovation for plucked-string instruments. If it's got that pinch in the middle, you can pretty much use any bracing scheme, any wood variety, any scale length or any number of strings, and it's gonna sound like a guitar. It might sound awful, but it'll sound like a guitar. There is something magic, though, about the sound of guitars from the era before fan (or X) bracing. I think there is still some gold to be mined from revisiting those early concepts.

It's interesting that you came across a modern, Torres-style classical with ladder bracing, and most interesting that it sounded like a fan braced top. Go figure. It seems there are as many was to build a guitar as there are luthiers! Ain't it grand?

[QUOTE=CarltonM]

Years ago I wondered why lutes and guitars, given similar bracing styles, woods, and strings, sound so distinctively different from each other. My first thought (befitting a novice) was the bowl-shaped body of the lute. Later, I realized it's largely a result of the narrow waist of the guitar.[/QUOTE]

Hey Carlton,

I'm not so sure I agree with your premise. I think there are many variables, and possibly some of the reasons for the lute's "silvery" sound is bridge placement, neck mass, soundhole size and position, as well as body shape. Also lutes use rather light strings compared to guitars.

I can partially back up my position by pointing to an experimental build of mine. I call this body style Zen (long story), and this one is the second prototype.



My research into classical soundboard acoustics indicated that a traditionally braced modern classical guitar's upper bout is largely acoustically inactive. So, I got to thinking, rather than build a guitar with a cutaway, why not just truncate the entire upper bout? So that's what I did. This guitar's neck meets the body at the 17th fret.

It is tradionally constructed in every other way. I used a standard Torres-style 7-fan pattern for the soundboard, although I did have to add a couple of angle braces between the neck heel block and the bottom tonebar to keep the guitar from folding up.

As you can see, it has only the vestiges of a waist. I felt it needed something there just so one could rest it on one's leg. But it doesn't have a waist (or upper bout, for that matter) in any traditional sense.

The sound? Actually, the guitar sounds surpisingly good. It is quite loud and has a pronounced Spanish quality to it. And also surprisingly, the basses are quite strong and resonant. They are not quite as deep as one would expect with a large classical, but they're not thin by any means.

Actually, the first prototype I built sounds much different, and I believe it does because it has a 24-fret fingerboard, which necessitated that I relocate the soundhole. So, I installed two soundholes in the guitar, whose area equaled that of a single soundhole. It sounds like a nylon string, but it doesn't have that classical guitar sound, if that makes any sense. Not bad, just different. After completing it, I suspected that the twin soundholes were the reason for its rather peculiar sound quality, and I believe I confirmed that by building another with a traditional soundhole placement.

Incidentally, here's a pic of the first Zen:



Best,

Michael

_________________
Live to Play, Play to Live

[QUOTE=Michael McBroom]

I'm not so sure I agree with your premise. I think there are many variables, and possibly some of the reasons for the lute's "silvery" sound is bridge placement, neck mass, soundhole size and position, as well as body shape. Also lutes use rather light strings compared to guitars.

[/QUOTE]

I agree, as with all things luthery, it's all a matter of small details. The bridge placement on early guitars and lutes was very similar, towards the tail block (see the pics above). They only started to move the bridge up the guitar when it was felt essential to have 20+ frets available. Many people, me included, think the 12-fret 000 has a sweeter sound compared to the 14-fret OM. What would a 10 fret steel string sound like, moving the bridge further back?

I think the main contributor to the lute's sound is a combination of the heavier neck, yes 13-course lutes sound more 'silvery' than six couse ones and, the gut strings and frets. I can hear the difference between my 7-course and my 10-course lute with its heavier neck. I am currently halfway through building a 13-course so I'll see if that is more so. I'm also part way with a copy of the 1700 Strad 5-course guitar, which has a very similar body shape and bridge position to the 1780 6-string above. For the next couple of years I plan to only build early instruments so I might have more of a handle on it then.

I believe we have a lot to learn from the early instruments that can be applied to modern day. Just because Torres or Martin did something doesn't mean that we all have to slavishly follow.

Michael, lutes only use light strings compared to modern guitars they use the same strings as the early guitars, and violins.

Colin

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

My understanding is that the viol and violin both came out of the guitar, not the other way around. Small GLOs (Guitar Like Objects) were used in Spain early on, and when the idea of the bow came in around 900 or so they applied it to just about everything. You could take the frets off your vihuela, and since the fingerboard was just a veneer held by the tied frets that would come off too. Put a wedge under the fingerboard, stand a tall bridge up on the top of the thing, and tie the strings to a leather 'tailpiece' that hooked to the strap button, and you had a vihuela de arca.

The upper bout of the top might not be doing much, but you sure can't say the same for the air inside! There are some very useful relationships built into the air and wood resonances of good guitars that rely on that upper bout, and I don't think that's by accident. A guitar without upper bouts can sound good to me, but it doesn't sound as much like a 'guitar' as I'd like.

This seems to be the case for most folks: pear shaped, bell shaped, lyre shaped and so on, the variations come and go through history, but the guitar always seems to go back to the waisted shape. There's got to be a reason.

Michael...It's been my (limited) experience that "guitars" without a waist and upper bout just don't sound like guitars (think bouzoukis). I don't doubt your word that you've managed to build one with a guitaristic sound, but I think it's the exception to the rule. Now, I don't mean that those un-waisted instruments inherently sound bad, just not like a guitar. Here's what I've heard: As the upper bout shrinks, or the waist expands, the sound shifts to the upper harmonics or to the fundamental, respectively, and, as both the bout and waist disappear, it becomes something that doesn't sound like a guitar.

Colin...You've certainly got much more experience than I in these matters, and I'm not trying to dismiss your well-thought conclusions offhandedly, but it's my contention that if you put a guitar neck on a lute, it'll still sound like a lute. As well, if you put a lute neck on a guitar (or some arrangement with similarities, e.g. a harp guitar), it'll still sound like a guitar. I'm convinced the reason for that is the guitar's narrow waist. I've been wrong before, though, so I'll keep an open mind. I'm quite interested to hear details, as time goes on, about your quest to build early-style instruments. I hope you can get plenty of in-progress photos.

Alan...You may well be correct about the guitar/viol genesis. As I've read it, the evolution of guitars is quite fuzzy in their earliest years, though it seems clear that all stringed instruments decend from harps. The earlist bowed instruments, if I'm correct, didn't have carved tops, and were shaped more like what we think of as guitars than violins. They were quite small, though, and, from reproductions I've heard, didn't sound like what either of those instruments became. The missing link (in the western world) seems to be the vihuela, of which, I think, there's only one complete example extant. Years ago, I heard a recording of a replica of that instrument, and with its wide waist and shallow body it sounded more like a dulcimer than a guitar or viol. Okay, enough speculation--it's not something I'LL ever be able to solve. Thanks for your input, Alan.

This is really what I love about guitar building -- the infinite set of variables. The incredibly broad pallette that will most likely respond favorably as long as good building techniques are followed.

Now, I realize to convince you folks, I'm gonna have to record my Zen and post an mp3 somewhere so you can hear it for yourselves. Hey, I was as surprised as anybody. And I've been a classical player for over 30 years. Surprised and ecstatic. Next, I need to "proof" the build, that is, I need to see if I can duplicate -- or come close -- to the acoustic qualities of this second prototype. If I can, well, I won't need to explain the why and how, all I'll need to worry about is the "what".

Best,

Michael

_________________
Live to Play, Play to Live

[QUOTE=Michael McBroom] Now, I realize to convince you folks, I'm gonna have to record my Zen and post an mp3 somewhere so you can hear it for yourselves. Hey, I was as surprised as anybody. And I've been a classical player for over 30 years. Surprised and ecstatic. Next, I need to "proof" the build, that is, I need to see if I can duplicate -- or come close -- to the acoustic qualities of this second prototype. If I can, well, I won't need to explain the why and how, all I'll need to worry about is the "what".

Best,

Michael
[/QUOTE]

Cool! Go for it!!

I think it is dangerous to say that a lute sounds like a lute because of one or two individual elements. It sounds like a lute because it is a lute! The same is of course true of the guitar, its all down to the small details coming together as a whole.

The early guitars I have played, mainly from the collection at the Royal College of Music here in London,(where I sometimes play, rather badly, in an early music consort), although certainly sounding like guitars, also have something of the lute sound to them, which I have always put down to the similar gut frets/strings and the rear bridge position, but I may be wrong.

There are pics of a couple of my lutes on the forum somewhere.

I think that those of us who don't earn a living at those business and a market to satisfy have a duty to experiment.

Colin

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

Colin:
I have a market to satisfy, and I still experiment. It sure cuts into the income, but it's just so much fun....

One thing that makes the lute 'lutelike' is the back, which is almost entirely a reflector, despite being so light. Modern wooden guitar backs tend to move some (and sometimes a lot!), and help to color the tone, particularly in the low and mid ranges. Lute backs don't move much at low frequencies. I haven't had a chance to check out one of the old bowlback 5-course guitars yet. Ovations, of course....

I think they found another vihuela aside from the Jaquemart-Andre instrument, in Peru. There was a thriving instrument 'industry' there after the conquest. From what I understand it's pretty crude, but definitely a vihuela. There's some question as to whether the one in Paris was meant as a musical instrument. Romanillos pointed out that it exactly fits one of the requirements of the old guild master's exam: to make a 'large vihuela in many pieces'. That one may have been such an eye-popper that it got put on a shelf and hence survived when the players instruments didn't.

I, too, have noted what Carlton has; a tendancy for guitars without a pronounced waist to lose mid-range sound relative to the treble and bass. It seems to have to do with the air resonances I mentioned before. It's complicated: the location of the soundhole relative to both the upper end of the body and the waist also gets into the act apparently.

I must respectfully disagree with Carlton about 'all stringed instruments descending from harps' except in a very general sense: the musical bow is a sort of 'harp', and is probably the oldest stringed instrument. True harps in the accepted organological sense have strings that pull upward on the soundboard. Lyres, which differ from harps in having the strings parallel to the soundboard, would be more like it: the way the string drives the soundboard is different. If you stuff an inflated bladder between your bow and the string as a soundbox you've got something more like a lyre than a harp. Early skin-gourd-and-stick bodies, which lead to the banjo directly and the lute by a more circuitous route, could be set up in lots of different ways. Look up the west African 'kora' for a cross between the lyre and the banjo. I note that the kora is often called a harp, although it's not. I know this is nit picking, but heck, what's the use of scholarly research if you can't fight about it politely over tea in the faculty lounge?   :)

Colin...You're getting a big "atta boy" from me for your desire to experiment! Once again, take many pictures! Okay, if you're feeling especially frisky, try this--make a lute in every way like a guitar (fan, X, ladder, hybrid--your choice), except the body shape (top and back). Or the reverse--build a guitar in every way like a lute, except for the body shape. There may be some crossover in the sound of either, but I still think the body shape will win out in which instrument it sounds most like. I know it would be a LOT of work to prove wrong some nut in small-town U.S.A, but it surely would be interesting to hear the results!

Alan...Yep, you're right, I was much too all-encompassing in what I was including in the "harp" family. I was thinking of the lineage from the bow to the lyre, forgetting all the side trips to which human ingenuity has taken us. Thanks for the lesson!