Lutherie & Guitars – Page 2

Titebond vs. Hide Glue

September, 2013

Glue. All woodworkers use it. And what can one say about it that hasn’t been said already? — that is, aside from jokes like “My wife gave me a book titled The Complete History of Glue for my birthday. What was it like? Heck, once I picked it up I couldn’t put it down…”

Well, the principal function of any glue — outside of considerations of working time, adhesive strength, and materials compatibility — is simply to enable one surface to stick to another. Period. Therefore if the glue has been appropriately selected for the task at hand and applied correctly, all glues work satisfactorily: the glued parts all adhere together for a long time without bleeding, creeping, breaking down, discoloring the woods, or otherwise failing.

For woodworkers in general, hide glue and fish glue were the only glues available for a long time. More recently, synthetic and chemical glues have been developed which are more convenient to use, give extended working time, are waterproof, etc. For the general woodworker who is not committed to using epoxies and such for specialized purposes, Titebond (and the other aliphatic resin glues which are sold under a variety of names) pretty much heads the list of modern favorites. It works every time. The somewhat less convenient hide glue (made from animal hides and hooves) is still used by purists, craftsmen, and traditionalists. It works every time as well. Elmer’s White glue, that staple of school projects, is a polyvinyl glue which never gets really hard; hence most woodworkers don’t use it on serious projects.

The Titebonds and hide glues are certainly the favorite adhesives when it comes to making guitars despite the latter’s minor inconveniences of preparation and quick setting time. On the whole they give equivalent results, but with one significant difference. This is most noticeable to repairmen and restorers — those whose work requires them to take glue joints apart, or to deal with failed joints. The difference is that of destructive vs. non-destructive reversibility. What that means is that one can take a hide glue joint apart (if one knows how, and if one is willing to be patient) without removing of any actual wood. One cannot take a Titebonded joint apart without losing at least a little bit of the original wood: one undoes the joint and then needs to do some sanding or scraping to expose fresh wood. This might not seem like an important consideration in most woodworking, and it is pretty much irrelevant in factory-made guitars: there’s enough wood in these so that you can lose 1/64″ of thickness and still be all right. But in craftsman-level guitar work, which can allow for more carefully titrated and thicknessed parts, the loss of a few thousandths of an inch of wood may make a difference in sound.

There’s also a second consideration when it comes to doing repair and restoration work on a valuable collector’s instrument. In this realm, having the instrument be as fully original as possible is desirable: alterations and modifications of any kind can devalue the instrument. So, in these cases, it is preferable to find that the guitar has been held together with hide glue: the parts can be taken apart and reglued while maintaining fidelity to the original sizes, thicknesses, and specifications of the woods, not to mention the original intent and methodology of the maker. One can understand that a damaged Louis XIV chair that’s been epoxied together wouldn’t be considered authentic — and it would be priced accordingly.

I’d always assumed that Titebond was water soluble (after all, it dilutes easily with water when it’s still liquid) and that it could be removed completely, after it had hardened, if one wanted to spend enough time sponging and wiping it carefully away with warm water. It’s exactly what one can do with hide glue. But Titebond is a synthetic glue, not an organic one, and it has unexpected staying power. I should add that with both of these glues one heats a joint that is to be undone, so as to soften the glue and help it release its hold.

Titebond is only partially un-doable. This property of it impressed itself on me in an interesting and accidental way. I’d made a pencil holder a long time ago by pouring some Titebond into the bottom of a recycled plastic jar that had a rounded bottom edge and then dropping a bunch of ball bearings in for ballast — to ensure that it was heavy and stable enough to not tip over once I filled it with pencils and pens. The Titebond soon hardened and rendered the ball-bearing ballast permanent, and the jar held my pencils and pens nicely. Some years later I was able to afford a real pencil holder, so I transferred the pens and pencils and filled the old jar with hot water so as to melt the Titebond and reclaim the ball bearings. I thought it would take a few days of soaking for the Titebond to give way; the ball bearings were stainless steel and wouldn’t rust.

Well, to my surprise, the Titebond did soften but it didn’t dissolve at all; it was still there after three weeks of continual immersion in warmed water. It softened enough that I could squeeze the ball bearings back out, but what remained was a honeycombed, spongelike mass of rubbery aliphatic resin that looked like a coral reef — and that hardened up rock solid again as soon as it dried out. (See the accompanying photos.)

As it turns out, it’s not only the composition of the glue that makes the problem for repairmen and restorers. It also has to do with how the adhesive achieves its results. In the case of the newer glues such as Titebond, these grab onto the materials they come into contact with by means of penetrative adhesion: they sink into wood fibers and grab hold. And once there, they want to stay. The upshot is that undoing such a joint usually results in some splintering, tearing, or pulling up of wood fibers, and thus leaving a rough surface that will itself need to be smoothed before any regluing can occur.

In addition, whether or not there’s been pulling away of wood fibers, some of the Titebond will remain on the wood surface and, as I pointed out with my ball-bearings experience, Titebond will not simply wash away. Thus the usual way of post-Titebond surface preparation is to sand or scrape at the roughened sections (imagine trying to sand or scrape cold honey off a piece of plywood; it’s the same thing) until smooth wood is reached; then, one reglues.

Hide glue, on the other hand, achieves its results by molecular bonding. Titebond won’t hold very well onto something it cannot penetrate, such as glass. But hide glue will. In fact, it’ll hold on like a barnacle on a ship’s hull. In the old days before sand blasting, glass was decorated by covering the to-be-textured-or-highlighted area with hide glue; once this dried the hide glue was chipped off with a chisel and a hammer — and it would take some of the glass with it. The contrast between this newly chipped surface and the smooth original surface of the glass is how lettering and decoration in that medium used to be achieved! The really interesting part of this is that, molecular bonding aside, one can wash hide glue completely away without affecting the surface it has been applied to. Like campers, hikers, or guests with an ecological consciousness, hide glue can disappear without leaving any trace or litter behind it.

The Taku Sakashta Guitar Project

February, 2013

The guitar making community lost a valued member on February 11, 2010, when Japanese-American luthier Taku Sakashta was killed outside of his workshop in Rohnert Park, California. I knew Taku for 15 years and was his colleague and friend. He was a uniquely hard-working individual as well as a luthier of rare talent. Those familiar with his work know that Taku brought a very Japanese aesthetic to it, such that his guitars were imbued with a cleanness of line that echoed the sensibility of the traditional Japanese rock garden. Taku’s workmanship was imaginative, original, and faultlessly CLEAN.

Taku’s murderer was caught, tried, and sent to prison for life. In the aftermath of these events Taku’s widow Kazuko sought to put proper closure to her husband’s affairs; so she asked a number of Taku’s closest luthier friends to take on and complete a number of guitar commissions that Taku had begun. I accepted one of these, and am close to being finished with it. It’s a guitar made mostly by me, with Taku’s woods, using Taku’s molds and templates. The result is the world’s only Somogyi-Sakashta guitar. It is presently in the hands of Larry Robinson, who is doing the final inlay work; he and Taku had already discussed an inlay motif before Taku died.

I don’t want to make this narrative very long; the whole point of it is to just announce the (almost) completion of this special project. But if anyone wants to know more of the facts and details please get in touch with me and I’ll give them the longer story.

Also, if anyone wishes to send a donation to Kazuko at this date, the gesture will be appreciated as much as if it had been offered nearer Taku’s death; the help is still needed. For those wishing to send a check or money-order, it should be made out to either Kazuko Sakashita or to Taku Sakashta Guitars (NOTE: ‘Sakashita’ is pronounced ‘Sakashta’): the account is in both these names. Donations should be sent to: Wells Fargo Bank c/o account No. 7478-148203, Elmwood branch, 2959 College Avenue, Berkeley, California, 94705. For those wishing to send a wire transfer of funds, it should be sent to the same account at the same bank, under the same name, and to the wire transfer-routing ABA number 121-000-248.

For those wishing to send woods, tools, materials, or anything else that cannot be sent into a bank account, luthier Tom Ribbecke has volunteered to be a repository of such more concrete donations, until they can be sold at auction together with Taku’s tools and woods. Todd Taggart of Allied Lutherie has generously volunteered to deal with that. Shipping of these donations should be made to Sakashta Memorial Fund, c/o Ribbecke Guitars, 498-D Moore Lane, Healdsburg, California, 75448. Tom gave me permission to also pass on his work phone number for anyone who feels the need to call him in regard to these matters: it is (707) 431-0125.

Sincerely, Ervin Somogyi

Werewood

February, 2013

I’ve been making guitars for a long time. My approach to the selection of the topwood (which is commonly agreed on as being the soul of the guitar) relies on a favorable stiffness-to-weight ratio — more so than on the grain’s evenness, count, or color. The wood’s weight is critical to me: it’s half the formula. I’ve sorted through uncounted topwood sets in the last forty-plus years and the range of their densities has never failed to impress itself on me. The same has also been true of the many piles of spruce and cedar planks I’ve sorted through and made selections from. I’d handle planks that were so heavy that they seemed fresh-felled and still full of water; they’d be next to planks that were so light that you could sneeze and they’d practically blow off the pile. These woods were of comparable size and had been kiln-dried together, so the moisture content would have been the same. I assumed that this disparity was all normal and natural — but it was only recently that I’ve learned of one of the mechanisms by which Nature produces such variety. I came upon an article written by Ernst Zurcher (with an umlaut over the “u”), a Swiss forestry expert, that explained how wood retains different weight, durability, and working properties when it is felled in synchrony with various phases of the moon.

That article is titled “Lunar rhythms in forestry traditions: lunar-correlated phenomena in tree biology and wood properties”. Zurcher wrote it for Wood Sciences magazine, HG F.21, c/o the Department of Forest Sciences, Swiss Federal Institute of Technology, Zurich, ETH-Zentrum, Zurich CH-8092, Switzerland (email: ernst.zuercher@swood.bfh.ch). Zurcher, it turns out, has written extensively on this fascinating topic.

Zurcher’s article, focusing as it does on the matter of timing in tree-felling practices, gave me an insight into the variation in woods’ mass that I’d long noticed. Traditional European forestry practices depend on a mindset of selectivity that is not possible for modern commercial lumbering businesses to even consider: these clear by the acre or square mile, and certainly not only during certain phases of the moon. European woods that are purposefully felled in relation to the moon’s cycles are in fact called “full moon wood”, among other things. Somehow, I seem to want to call this material “werewood”. I’ve also discovered, since reading Zurcher’s article, that there are lots of people who know about such wood and have known about it long before I did.

Regardless of what such wood is called, Zurcher’s thesis is this: Since before the time of Christ, foresters have noticed that the woods they cut yielded different working and stabilizing properties, in direct correlation with where in the lunar cycle those woods are felled. Woods cut during the full moon, the new moon, or the waning moon, have consistently different characteristics. Therefore, a number of especially advantageous uses for timber could be correlated with specific felling dates. [NOTE: Technically, proper assessment of felling dates also includes the moon’s cycles of height-trajectory with respect to the earth’s horizon, which shift from high to low and back again during the lunar cycle. Also, besides the phases of the moon and its height-of-travel over the earth’s horizon, the practice of paying attention to the felling date of a wood has also included which sign of the Zodiac was dominant at the time. Wood-cutting practices in places as diverse as Bhutan and Mali follow these “rules”. No, I’m not making this up; read the article.]

Zurcher points out that this body of empirically collected wisdom applies to a range of practical wood uses as diverse as house construction, roof shingles, wooden chimneys (well, they had them in the old days), barrels for storing liquids, boxes for storing foodstuffs, fuel (firewood), plows, transportation of felled woods via river floatation, and even musical instrument soundboards. Furthermore, the general rules for felling woods seem to be very similar across the continents. Whether in the Alpine regions, the Near East, in Africa, India, Ceylon, Brazil, and Guyana, these traditions all seem to be based in matching and independent observations. Zurcher quite reasonably points out that in the past, people had more time and more peace and quiet in which to observe how things work; indeed, such knowledge would have been vital to them.

Interestingly, while the empirical knowledge gotten through centuries of hands-on forestry practices has necessarily resulted in a body of oral tradition, peasant wisdom, and folklore, there’s also a significant body of historical writing in which lunar rhythms (over and above the cycles of the seasons) are mentioned as having an influence on the growth, structures, characteristics, and properties of plants. For instance, the Roman statesman and writer Pliny had advice to give on tree cutting, as well advising farmers to pick fruit for the market vs. fruit for their own stores at different phases of the moon: for the former, fruit picked just before or at the full moon would weigh more; for the latter, fruit picked during the new moon would last better.

The variations in wood density that I’ve mentioned noticing make sense within the context of modern vs. traditional wood felling practices. Today, loggers will work a forest, stand, or acreage indiscriminately, until their quota is met. The job might take weeks or months. But then, leaving a denuded hillside, they’ll move on to another patch of land and do the same. Selectivity is per acreage and tonnage, set by commercial considerations and not per specific intended use of the wood harvest. This contrasts sharply with the traditional selectivity that would have been the rule in any aware, non-industrial community of foresters: you go in and select a limited amount of wood to be used for specific purposes; you don’t cut indiscriminately and ship out by the lumber-truckfull. You take what you need, until the next trip into the forest. It’s easy to understand that these different mindsets would include or exclude ancillary, contextual, environmental, meteorological, commercial, and/or scheduling concerns.

Concerning Somogyi Knockoffs

December, 2012

In Japanese:

It has come to my attention that there have been some guitars recently introduced into the Japanese market that are using my “carved Carp top” design. They are doing so without my permission.

I am very much concerned about these knock-offs. I want to make it clear that Somogyi Guitars is not affiliated with those instruments and, I repeat, I have not given my permission to use my particular rendition of the carp design.

I understand that the carp is a traditional Japanese icon and that I am not the originator of that specific carp image. But I am the originator of that particular and specific artistic use of it on a guitar. I believe that my adaptation of that specific carp image to a guitar, in the way that I have done, is widely known and associated with me in Japan.

I am at present asking the company involved to immediately stop manufacturing and selling their guitars using my design in such a way as to create a similarity with any of my instruments.

I hope they will understand and honor my request and take the necessary steps to correct the problems.

Using Wenge as a Guitar Wood

November 30, 2012

Brazilian rosewood, that traditional “Holy Grail” of fine guitar making woods is getting scarce, expensive, and — with legislation such as the Lacey Act coming to the fore in recent years — illegal to have unless one has the legal paperwork to show its age, provenance, and legality to be allowed to cross borders. Therefore, in view of severe restrictions in supply and use of traditional guitar making woods, suppliers to the guitar making industry are offering new, supposedly more sustainable guitar making woods that no one had heard of ten years ago, that come from countries that half of us cannot find on the map. All of these woods, of course, are marketed as being desirable and adequate substitutes (availability, good grain, figure, color, dimensional stability, price, etc.) for the traditional materials.

In my view, some are and some aren’t. As a guitar maker, my own preferences are for woods that are “live” rather than not, regardless of their grain, figure or color. What that means is that one can elicit a live and musical tone from a particular slice or chunk when one taps on it. Some woods can make sound on the order of thummmmmmmm or thimmmmmmmm (ginnnnnnnng, gonnnnnng, pinnnnnnng or ponnnnnnnng also work; I think you get the idea), with bell-like sustain; others go “thwick” or “thud”***. I mean, the reason some woods are called tonewoods is because they literally produce a musical note. And this quality, when used to make a guitar soundbox, will make a better and more acoustically active guitar than would be the case if the woods used made some kind of thud or thunk when sounded. Such woods are fine for making furniture. If they’re to be used in guitar making, though, then a perfectly reasonable course of action is to focus on the visuals instead of the acoustics. There are “live” woods that look rather plain, and there are “dead” woods that look like Raquel Welch in 3-D. The flash and beauty of the latter have an obvious appeal and many guitars get made because their looking gorgeous will be a strong selling point. As much to the point, when considerations of tone and appearance vie for customers, heated discussions about the good points of this or that combination of materials will occur and a variety of woods will be brought out as being “as good as”, “acoustically responsive”, “high quality”, “surprisingly good”, “improved by patented methods of treatment”, “a comparable alternative”, “now used by the so-and-so factory in their higher end guitars”, and so on.

My own searches have brought me to wenge (pronounced WHEN-gay). It’s a dark, purplish-brown colored African hardwood that has long been used by bowl turners and cabinet/furniture makers. For some reason, no one seems to have thought about using it for guitars yet — so it’s relatively cheap. (Once something catches the attention of the buying public its price goes up; with guitar making woods this rise can be quite dramatic.) The thing that appeals to me about wenge is that it is very live. That is, when you hold a piece of it up and tap on it — i.e., if you’re holding it in such a way that you’re not damping any of its vibrational modes — it’ll ring like a piece of glass, plate of steel, or a crystal brandy snifter. This quality is known as “vitreousness”, which literally means “glasslike-ness”. And wenge will make such a sound.

Wenge’s vitreousness is a function of the wood’s being brittle on the level of its cellular structure. In fact, it’s that very brittleness that makes the vibrational action, and the sound that this produces, possible. The brittleness that is a plus for sound has a mechanical downside, of sorts, in that the wood cracks easily if it’s mishandled (just as glass does), and it gives one splinters if one is careless with it. It can also take more patience to bend, because brittle woods resist bending easily. I repeat, however, that it is this very potential for cracking that puts wenge in the same category as that most prized of traditional guitar making woods, Brazilian rosewood. Lovely, alluring, and live though this “holy grail” wood is, it has also earned a reputation for being subject to cracking. Sound vs. fragility: it’s a tradeoff for which there are few solutions so long as one wishes to use that material — and the solutions involve (1) overbuilding so as to minimize fragility (which comes at the expense of tonal response), or (2) mindful treatment and care in the making, in the handling, and in the using. The former gives you structural stability and less sound; the latter gives you structural fragility and much more sound.

While the acoustic properties of a given wood might make it a joy for a guitar maker to work with, marketing a new wood can be tricky. No one will have heard of it, much less had experience with it; the buying public will be suspicious of, and resistant to, accepting it. It’s a bit of an uphill slog until it “catches on”. This has certainly been my experience. I’ve made five of these guitars by now and am working on my sixth. As I said: it’s wonderfully live; but most of my customers still want Brazilian rosewood. That’s fine; but wenge is a really good alternative for anyone who is willing to be open minded. And it makes the guitars less expensive.

Finally, I have to add that making guitars that sound good, using wenge for the back and sides, should not be much of an impediment to younger guitar makers who are still establishing their reputations and their styles. As I said, it’s a good wood, needing only a good advertising campaign behind it. It is the more established guitar makers such as myself who, already having reputations for using this wood or that wood, or having a certain by-now-familiar style or feature associated with their work, who meet the greatest resistance to anything new. In my case, everybody wants me to make the same things for them that I’ve been making for my other clients; the traditional woods and designs, after all, have their good track records. An example of this factor would be that I’d expect to have a hard time selling a guitar (that I made) that looked like Grit Laskin’s work, well executed though it might be; why would anyone buy a Laskin knock-off from me when they can get an original from him? And I’d expect Mr. Laskin to have an equally hard time selling a guitar that looked like my work; why would anyone buy a Somogyi knock-off when they can get an original from me? Just so with woods and other departures from our norms.

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*** These sounds are onomatopoeic. Onomatopoeia is when a word replicates something of the very sound that it’s identifying. Onomatopoeia is useful, in spite of the fact that if one overuses it one sounds like a six-year old. But in fact, many “sound” words such as boom, crack, boing, thud, tap, ding-dong, smack, roar, clink, thump, clang, whap, bam, zip, hum, buzz, gong, snap, gurgle, ka-chunk, ka-ching, scratch, whoosh, zing, pow, ting, bark, meow, hiss, pop, twang, shriek, puff, clank, beep, snip, clip, chop, thunk, boinnnng, flap, squawk, screech, puff, tick-tock, bop, creak, glug-glug, ring, whack, moo, ruffle, oink, spank, swish, growl, tinkle, rip, rumble, squash, cock-a-doodle-doo, crash, squish, ack-ack, clunk, zap, whizz, whirr, bang, murmur, cough, drip, splash, shpritz, zoom, flush, clap, slap, slam, ah-choo, snort, chortle, giggle, gulp, gasp, shuffle, bip, ring, and thud are onomatopoeic. Try reading this list out loud: it’ll remind you of someone falling down a long flight of stairs and hitting some pets along the way. As far as having a discussion about something like music goes, the nouns and onomatopoeics are fairly straightforward; it’s the adjectives for sound (smooth, liquid, smoky, complex, transparent, rough, golden, dark, even, cloying, colorful, dull, transient, fruity, present, sweet, sharp, mellow, full-bodied, dry, light, airy, impressive, etc.), that get us into the most trouble.

FAQ #8: Flat Vs. Domed Tops

September 22, 2012

Q: In your book you recomend 30′ for a top radius, if one decides to buy a commercialy made disc. On the other hand I saw that James Goodall and Robert Taylor use 50′ and 65′ radiused dishes and Jim Olson & Kevin Ryan make FLAT non-radius tops. Olson said that he feels that these produce more responsive tops. So why, exactly, do you recomend a 30′ one? Wouldn’t a 65′ one be better since it is closer to being FLAT?

A: It’s a question of balancing various factors — very similar to a cook’s gauging how much of this and/or that spice or flavoring to use in making a dinner.

In the guitar (instead of carrots, lamb, and oregano) the ingredients are the string tension, the torque from the bridge, the mass of the braced top (which is arrived at by any combination of top thickness and bracing mass), top bracing and reinforcement (that is, the pattern and layout of the braces, as well as their profiling and height), and desired target sound (the resultant mix of monopole and dipoles, as well as sustain and dynamics).

There is no “correct” way to make a guitar. If there were, they’d all sound the same — just as if there were only one recipe for making French onion soup: then all French onion soup would taste exactly the same. In the biological realm, it would be equivalent to having every wife, husband, boyfriend, girlfrend, son, daughter, etc. be clones. So let’s forget “the one best way” of doing something complex.

Jim Olsen holds that a flat top is the most responsive. Very well. But what, exactly, does that mean? Does this not have something to do with how thick and/or stiff the top is, or how it is braced? And how it responds to the mechanical pull of the strings? I suspect that it does. So if we were to imagine a VERY thin top that is made flat, it would be easy to imagine it buckling or caving in under the pull of the strings… unless the bracing were beefy enough to make up for the weakness of such a flat plate. In other words, you could make that flimsy face hold up by adding more reinforcing.

You could also/instead make that flimsy face hold up better by putting an arch or dome into it. Arched structures are stiffer and more stable than flat ones — just as a pointed or arched roof on a house will hold up to rain and snow better than a flat one. Western architecture took a mighty step forward when structural doming became possible: the materials themselves — rather than supports, trusses, beams, and buttresses — achieve the required structural integrity, Analogously, if you put a dome or arch into the guitar face, you could use less bracing and achieve the same stiffness with fewer materials (i.e. less mass).

Less mass is good; it means that the strings have to strain less to coax sound out of the top. The strings need to work harder to get sound out of a heavy top — exactly as a horse has to pull harder to make a heavily loaded wagon move. You can appreciate that different archings/domings induce different amounts of stiffness into a plate. As can different thicknesses of that plate. And so can different sizes and layouts of braces. These are, in fact, the three main ingredients of top-making, exactly as flour, water, and eggs are three main ingredients in bread making. And in both guitars and bread the ingredients can be mixed or combined in different ways to produce a successful product. In the guitar this goal is: a top that is intelligently constructed and reasonably lightweight (which goes to sound), and also able to hold up to the pull of the strings (which goes to long-term stability of the guitar).

In the guitar, ridiculously small (or small-seeming) amounts of these various ingredients can make a difference you can clearly hear. For instance, a bit more or less top thickness can offset a bit more or less doming. A bit more or less bracing can offset a bit more or less top thickness. And so on. Identifying and using only one of these factors as being “most important”, appealing though that idea is, turns out not to be realistic. If the guitar were a political construct rather than a mechanical one, then it would work best as a democracy in which every component is (not to make a pun) given its proper voice. To make one into a “leader” (in our sociopolitical sense of the word) is not what a guitar is all about.

An Amusing Experience

September 22, 2012

I want to tell you about an interesting experience I had a few years ago. A good many of you out there may well be able to relate to it.

Some of you readers may know that I play flamenco guitar. Well, in the best Shoemaker’s-Children-Have-No-Shoes tradition, I didn’t have a good flamenco guitar of my own for a long time; I was playing a borrowed cheapo. So, with friends’ benevolent prodding to motivate me (but that’s the subject of another article), I decided to make myself my own guitar. And I did. With great eagerness and anticipation.

When the moment finally came to string it up and play it, I was struck by what a magnificent bass response it had. My shop was then in a high-ceiling warehouse space, and this guitar’s bass absolutely filled that cavernous room. It made the air space resonate. It was like a Taiko-drum guitar. The bass was, in a word, simply awesome. It entirely overshadowed the treble end.

Unfortunately, a really good bass is not the sound that a good flamenco guitar needs to have. One wants something bright, zingy, penetrating, with the traditional flamenco rough edge. Where had I gone wrong? (Does this scenario sound familiar to any of you?) Technically, I’d built a guitar with a kick-ass good monopole, but not much cross- or long dipoles — although this was language I was to learn later; I was not familiar with such concepts at the time.

I spent some time pondering what to do. Shave the braces? If so, which ones, where, and by how much? Should I sand the top thinner? Again: where and how much? Should I put on higher tension strings? Or install a new fretboard with a longer scale? Or perhaps become withdrawn, eat compulsively, drop out of lutherie and realize my life’s secret ambition of becoming the first Hungarian-American sumo wrestler? Heck, I had lots of options. It also occurred to me that I could call some of my expert fellow luthiers and get some informed advice. It seemed, at least, a good way to get some consensus as to where to start. They’d know exactly what to do, surely.

I called noted authority Richard Brune; he not only makes classic and flamenco guitars, but is also a skilled flamenco guitar player. He’d certainly know how to fix this. So I described the guitar to him over the telephone, taking care to be as specific as I could be about sizes, measurements, thicknesses, etc. He took in my information and immediately told me that my braces were inadequate to the job; I needed much bigger braces. He advised me to rebrace the guitar in that way, or at least retrofit meatier braces in through the soundhole. I thanked Richard for his advice and hung up.

I’d hoped for an easier fix than to either futz blindly for hours through the soundhole; or retop the guitar; or remove the back, rebrace the innards, and then replace the back and then do refinishing. That’s a lot of work. Besides, it wasn’t as though the guitar were for an important client or anything. So I thought that I could perhaps get a second opinion — to at least force me to do this work by the sheer preponderance of advice. I called Robert Ruck, an internationally and deservedly noted Spanish guitar maker who also plays flamenco guitar. I’d known him, as I’d known Brune, from any number of G.A.L. conventions, private correspondence, phone conversations, etc. Many of you reading this will have attended their lectures, read their articles, and also met them.

Once again, I went through the process of describing my guitar to a knowledgeable expert; same guitar, same measurements, same parameters, same conversation. Robert took my information in, and just as quickly as Brune had given me his opinion, rendered his own: my braces were too big. According to him, I needed to shave the braces down drastically in order to gain a satisfactory sound. He offered to fax me a drawing — which he in fact did the next day — of a special brace-shaving tool that he’d invented for shaving hard-to-get-at braces through the soundhole; it was especially useful for shaving down the Spanish guitar’s diagonal braces — the chevrons that are farthest from the soundhole and the most impossible to get to. I thanked Robert for his input and hung up.

I’d hardly expected to get identical input from two independent luthiers; but this was ridiculous. My next idea was the obvious one: to call someone else and at least try for a consensus of two out of three. I needed more input. Whether I wanted it or not.

I happened to have a conversation with luthier Steve Klein the following week. Steve doesn’t make flamenco guitars — or conventional guitars of any kind, for that matter. Still, he’s a very smart, articulate luthier and a brilliant designer with years of guitar making experience behind him, so I mentioned the two conversations I’d already had about my guitar’s spectacular lack of tonal balance. I thought that Steve might have a useful perspective on my problem; after all, bass is bass and treble is treble and a guitar is a guitar, right?

Steve’s opinion, diplomatically rendered after I described my situation to him, was that my bridge design was faulty. In Steve’s opinion, I could improve the sound of my guitar in the desired direction by replacing the bridge with — I forget which now, since so much time has passed since this conversation happened, and I was a little shell-shocked anyway — either a lighter one or a heavier one. I thanked Steve for his input and said goodbye.

Armed with all this advice and support from some of the more prominent of my professional colleagues, I was, how shall I say it, not yet quite fully enlightened. The thought of hacking wood away from my guitar — or gluing wood on — here and there, hoping to strike gold through luck as much as skill, didn’t have much appeal for me. And, suppose I managed to destroy the bass response without improving the treble? Or even (God forbid) even improve it?! I agonized. But, I thought: I am a professional, am I not? Bottom line: I still needed to get at least some clarity on this matter. Understandably, however, I found myself a bit reluctant to ask for input from anyone else.

Right about that time I visited nearby-based luthier Randy Angella’s new workshop; Angella had been making lovely and really good sounding classic guitars for years, had then dropped out and gone into different work, and had more recently come back into lutherie. I thought I might get some ideas from him. But I wasn’t going to ask directly: I’d tried that tactic and it had been leading nowhere. I was going to sneak around and try to get a hint from whatever methods he was using.

Randy is a very nice man and is able to share freely of his knowledge and techniques. He was at the time making his guitar tops’ perimeters very thin — including the edge along the lower transverse brace, sometimes known as the harmonic bar; he was tapering the top on the bridge-side of the lower transverse brace, and leaving it full thickness past that brace. I took note of this. Unfortunately, as the wisdom I’d received to that point in time indicated that thinning the perimeter of a guitar face would loosen its “hinge” movement and help the bass, I couldn’t see that going in this direction was going to be of any help to me. I already had too much bass, and maybe I should have asked about Randy’s thinking. Bugfat.

I reviewed my options again. I could jump in and shave some braces. I could sand the top thinner. In both cases I’d simply need to figure out where and how much. I might have luck with higher tension strings; but they might make the guitar sound even more robust. Or lower tension strings: they’d give me a more delicate sound, surely. I could install a longer fretboard and scale; or a shorter one; this would be more or less the equivalent of experimenting with string gauges. I might dump the project and retop the guitar. Then, I could also leave town quietly. Yep, I still had lots of options.

I’d begun to get to know luthier Eugene Clark at about that time; he was living about fifteen minutes away from me. He and I got together at a local restaurant, after having had made on-again/off-again plans for some time. Eugene is almost legendary as a Spanish guitar maker, and, not surprisingly, the subject of my problematic guitar came up. Over coffee and dessert I described my problematic situation, and Eugene in turn explained his concept of the Spanish guitar to me: it is — in a nutshell — a thin film of lightly braced wood stretched over a spare framework of massive main braces that (1) strictly delineate its vibrating areas and simultaneously (2) sets the resonances of these areas by virtue of the level of introduced rigidity. As far as the face is concerned, Eugene’s idea of the most effective design is to have a thin, domed plate of topwood held up by a rigid perimeter and by rather substantial upper and lower transverse braces (i.e., the ones that straddle the soundhole) which are moreover fully anchored into the sides. That is, these braces aren’t scalloped at the ends — which weakens their attachment to the main structure, and hence their stiffening/load bearing capacity — but rather butted at full height against the sides, and then held in place on each end with a bracket. I showed him my guitar; Eugene immediately showed me something interesting: that by simply pressing on the guitar’s face with his thumb over the lower transverse brace, he could stiffen that brace — and the quadrant it served — sufficiently so that the tap tone became significantly altered. When he let go with his thumb, the original (and, frankly, thuddy and dull) sound came back; when he pressed down again, the top responded with a dramatically more live ping. No rebracing; no rethicknessing; but tightening the top up — even in this ad hoc and artificial way — made a difference that I could instantly hear. In dynamic terms, such a mechanical change toward brighter response would come at the expense of the monopole (which my guitar had in abundance); and it brought out more of the long and cross dipoles — which is exactly how a flamenco guitar ought to be functioning in the first place. I was very glad for this input.

In due time I went back to my workbench and reworked my guitar. I spent a day carefully removing the lower transverse brace through the soundhole. I did it carefully and cleanly. And I installed a meatier replacement. The toughest part was cutting the linings away; I had to do that to make room for a replacement brace that extended fully from side wood to side wood and whose ends I could glue brackets over. I had to cut two of my Japanese woodcarving knives’ handles way down to make the tools small enough to fit into the guitar’s body. I did a little brace shaving, but not much. Simultaneously, I did remove wood from the top selectively with sandpaper and a sanding block, so as to facilitate the dipole motions of the bridge. I reasoned that this additional operation would help further the phenomenon Eugene had showed me. Then I re-French polished the face.

It worked. I took this guitar with me to the next Healdsburg Guitar Festival — not to display, but to have and play after hours, to amuse myself musically. By then the guitar had settled in (as all guitars eventually do) and light reflecting off the face was revealing that the face was thinned to the point that one could see the “imprinting” of the braces underneath; I don’t think this had happened before; but the guitar hadn’t existed in its originally thicknessed state long enough for it to settle in, so I’ll never know.

Anyway, I signed up to do an open mic performance at one of the local coffee houses one of the evenings of the festival, and I played that guitar. To my surprise, a man came up to me after my performance and offered to buy that guitar from me on the spot. I’d never had such an experience before, and I’d certainly not expected to make a sale that weekend in such a way. But I did!

All in all, this had been a terrifically broadening experience, filled with surprises of all kinds at every turn. Lamentably, the world lost its first Hungarian-American sumo wrestler, but that couldn’t be helped. My thanks to all the people who helped me to learn something.

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This article has been previously published in American Lutherie magazine.

FAQ #7: Flat Backs and Arch Tops

September 22, 2012

Q: Recently I bought your books & DVD and I found one sentence particularly interesting: you mentioned that if a guitar with a normal flat back had an arched top, its dynamics would be unique. Can you please reveal from your experiences in which direction the sound will change, compared to that of a normal flat/domed top?

A: It’s an interesting question, and to my knowledge no one has yet made a guitar like this. Mario Beauregard of Quebec, on the other hand, has been making something truly new: nylon string guitars with arched backs and flat tops.

The arching of a plate stiffens it: it improves its stiffness-to-weight ratio. And, acoustically, it raises the plate’s pitch: its vibrational behaviors are shifted toward high-frequency signal — such as the violin has. A small highly domed plate is not likely to have a good monopole — that is, a good low end. Also, the greater the arch, the shorter the sustain is likely to be.

Cellos have a low end, and they have violin-like arched plates — but they are huge compared to a guitar. So part of what we are discussing is the SIZE of the plate, in addition to its doming vs. flatness. But it would be difficult to play a cello-sized guitar.

There’s another factor too: what wood the arched plate is made of. Traditionally, all arched-plated instruments (violins, violas, cellos, standing basses, and jazz guitars) have used spruces and maples — spruces for the tops, maples for the backs. Maple does not have much sustain compared with some of the woods used in guitars, especially Brazilian rosewood (although, in my experience of the maples, Eastern rock maple has the most, Western broadleaf maple has the least, and European maple — which is a sycamore — has some). Therefore, if we’re talking about a guitar with an arched spruce top and a flat maple back, it would likely have a sound characterized by a quick attack and a quick decay: bright, brisk, zingy, sharp, and not much sustain.

Sustain is not a factor in arched-plate and bowed instruments. They don’t need natural sustain: they will make sound as long as the player continues to scrape his bow over the strings. In the guitar on the other hand, because it is a plucked rather than a bowed instrument, the sound stops as soon as the strings do — just as happens with the banjo, lute, koto, ukulele, mandolin, dulcimer, harp, or harpsichord. [NOTE: the harp and the harpsichord are both excited by plucking action; the piano is excited by hammering action.]

It’s not likely that these traditions had such acoustic considerations behind them. The science of acoustics didn’t yet exist, and early European makers would of course have used the woods available to them — in this case the European alpine spruces and maples. They were a long way from having access to imported exotics from the New World. Also, in those days, the cost of labor was cheap and the cost of materials was high, so a thick plate of an imported exotic wood (that you’d carve down into an arched surface, and in the process wasting much of the wood) would have been quite expensive, compared to a thin plate of the same wood such as would eventually be used on guitars.

FAQ #6: Bracing, Thickness, or Both

December 18, 2011

Q: In my limited experience with classical guitars there seems to be a need to have a more flexible top on the bass side and a more stiff top on the treble side, giving the warm and low sound on the bass and more sustain on the treble, as well as preventing the percussive anvil sort of trebles . The flamencos seem to have a somewhat less flexible bass and a flexible treble side, which gives them a somewhat percussive sound with rapid decay in sound. This is at least consistent in the examples I have and have had the opportunity to play.

If one were to attempt to make a classical guitar as stated above would a change in top thickness to accommodate the additional stiffness required on the treble side be in order, or would changing or stiffening the bracing on that side be a better option than making a guitar with a top that is not of uniform thickness?

So…essentially, bracing or thickness or both?

– – – – – – – – – – – – – – – – – – – – – – – – – –

A: Your question addresses the primary issue of whether it is desirable to design a plate that relies on symmetrical design, or an asymmetrical one, for optimal functioning. The matter is clouded by the fact that some remarkably good guitars of both types have been made. Also, some pretty unimpressive guitars of both designs have been made. So there’s no clear winner, and I’m not convinced that the mere fact of symmetrical or asymmetrical construction is the most important consideration. I mean, if it were, one of these designs would produce consistently better results than the other.

As I read your question, I am translating it (to myself) into language that I am most comfortable with. So my answer might put a different spin on things than you’re used to. Let’s see if this makes sense to you.

To my knowledge, flamenco guitars achieve their characteristic sound by having looser, more flexible tops in general than classic guitars. Specifically, they are so loose that the monopole (the base) is discharged quickly — thus giving those instruments the characteristic traditional “dry” sound without a lot of sustained presence; their sound is more percussive. Usually, if one believes in asymmetrical construction, the treble side is made a bit stiffer than the bass side. In any event, compared to classic guitars, flamenco guitars have a more prominent cross-dipole. They are “looser” in that mode, in which the top moves side-to-side across the centerline and the bridge teeter-totters with one wing going up as the other goes down, and back. You can get a sense of this looseness by simply pressing down on one of those tops with your thumb: you will probably feel them “give’ fairly easily. You can also test for cross-dipole compliance by lightly putting one or two fingers of one hand on one wing of the bridge and lightly tap on the other wing with your other hand. You should feel a definite and instantaneous displacement as the bridge see-saws relatively freely. Classic guitars will be built less loosely, and will accordingly have less mechanical “give”. Neither one of these designs is “good” or “bad”, by the way; they are simply different — and different for a reason.

To my knowledge, these characteristics of flexibility and movement in a guitar top are best achieved by careful BUT SYMMETRICAL calibration of the plate — and I do not try to build any mechanical or dimensional asymmetry into my own guitar tops. But I acknowledge that other makers of successful guitars use dimensionally asymmetrical faces, so I’m inclined to believe that the motions of the cross-dipole (or any other mode) apply to a variety of architectures. At that point, the issue becomes that of basic calibrating so that one is “in the ballpark” and doesn’t overbuild or underbuild. I go into several detailed discussions of this concern in various chapters of my book The Responsive Guitar. You’ll undoubtedly find some of my ideas from there worth at least thinking about.

Your question addresses the question of whether it’s appropriate to add or subtract bracing in order to accommodate to changees in top thickness — as a matter of making material stiffnesses — and hence vibrational action — be consistent. The matter of achieving a balance between stiffness and/or looseness through top thickness vs. bracing mass is central to lutherie. And in this balancing act, there are two factors that inform my thinking.

First, in the traditional approach, if one were to make part of the top thinner, one would indeed want to “compensate” for it by making the bracing a little stiffer. This is assuming that the maker’s goal is to have AN EVEN GRADIENT OF MECHANICAL AND VIBRATIONAL STIFFNESS FROM THE BRIDGE TO THE PERIMETER, IN ALL DIRECTIONS. This is certainly my goal. In purely practical terms, this is surprisingly tricky to do until you begin to understand what you’re doing and have some practice at it; after that, it’s surprisingly easy. So an experienced hand and eye are really useful to have. I should add that, incidentally and technically, the gradient that I visualize in my work is only even in the sense that there are no lumps or irregularities of localized stiffness between the center and the perimeter; but it is not the same slope on all axes, in the sense of being identical. The longitudinal gradient is stiffer than the lateral gradient.

Be all that as it may, the second factor is, I think, just as important. It’s also interesting, subtle, and elegant — and obvious. So much so that it took me years to see it. It’s the “water running downhill” principle; you know: that water will find a way to run downhill regardless of trees, rocks, or irregularities of slope or terrain — because that’s the nature of water. In fact, such downhill movement of water cannot be prevented short of putting up a barrier or obstacle that exceeds the power of gravity over water.

Interestingly, sound energy is the same, except that instead of running downhill it wants to radiate off a guitar top — with all the freedom of water running downhill. It’s the nature of sound energy to dissipate into its surrounding medium, be it air or water. If we think of sound energy as seeking its easiest path “out”, as water wants to find the easiest path “down”, then it’s a short step to seeing physical unevenness in a guitar top as being analogous to unevenness in downhill terrain. And unless any of this unevenness is significantly huge, both water and sound will continue to flow and radiate. Tweaking any of the minor irregularities of slope, terrain, or structure will by no means stop any of the flow or radiation; they’ll find a way to get from here to there.

Let’s take a look at how this might work in a guitar. Let’s assume that you have a dimensionally asymmetrical plate, as you described above. And let’s further assume that the structure — irregularities and all — is “in the ballpark” as far as not undermining the monopole, cross-dipole, and long dipole. Or, saying the same thing with different words, that the irregularities are such that they allow the capacity of the plate to engage in these modes without messing any of them up). The top will flex and bend and seesaw and vibrate just as all the theories, diagrams and Chladni patterns suggest. The question then becomes: what makes you assume that such a top and its vibrational modes have to function symmetrically around the guitar’s centerline? Or that the various vibrating quadrants and subsection of the face will map out as being active with elegant evenness, symmetry, and consistency? I mean, no one expects water to flow downhill over a natural terrain in a straight, even, consistent, and predictably regular line, do they?

Your question cites differential side-to-side construction. This is the axis of the cross-dipole, which is (in theory) a see-sawing action around the centerline. If we were to imagine two kids on a playground see-sawing up and down on a teeter-totter, that device will be pivoting on its center point as a matter of the manufacturer’s design. But, suppose one of the kids is heavier than the other one? That would introduce an irregularity into the flow of their play. The manufacturer of the teeter-totter wouldn’t care about that, of ocurse; only the kids would. And to anyone to whom the kids’ fun was important, they could compensate for this disparity in mass (in the “playing field” or “gradient”) of that teeter-totter by simply adjusting the fulcrum point to a somewhat off-center position. Then, being better balanced, the kids could see-saw happily and without strain: same mass, same energy, same frequency, easier and more harmonious oscill.ation.

This is close to my sense of how the guitar works. To repeat, using other words: if there is sufficient unevenness in the top because of any design idea of the maker, and the design variable isn’t so huge as to throw a monkey wrench into the natural functioning of the guitar, then that “uneven” top will accommodate to the needs of the energy flow of that irregular structure all by itself. It’ll adjust, within some limits (of the natural capacity for flexibility of its woods), and perhaps wind up fulcruming, say, 1/16″ off the centerline. It can do that because the guitar lacks a fixed fulcrum in the way that a teeter-totter has one. Therefore, the vibrating quadrants of the top may be a little bit lopsided or asymmetrical in actual movement, etc.. But, as far as dissipation of strings’ energy is concerned, nothing has been prevented; it’s simply found its way out via an alternate path from what “the manufacturer’s blueprint” might have suggested.

This doesn’t fully answer your question yet, but my answer required me to have sketched in this background before addressing it specifically. This background, to repeat once more, is that tonewood that has been worked to more or less optimal dimensions has a certain innate flexibility of vibratory potential. There are no fixed fulcrums or vibrational nodes. And it may not matter that you’ve made an irregular plate — as long as you have not made it so uneven that you’ve pushed the plate past some limit of being able to perform its principal vibrational tasks.

So, to sum up: my answer to you is in four parts:

First, that yes, if you make a top thinner on one wing, which necessarily weakens it, then there’s a logic to adding bracing stiffness to it to make up for that weakening. I believe that one should aim toward at least some standard of evenness of physical/mechanical/tonal gradient if one’s goal is to make better and more reliable guitars.

Second: I believe that these maneuvers work most effectively if the top and braces are “in the ballpark” as far as optimal mass and stiffness are concerned — rather than the system being overbuilt as is often the case. Or underbuilt, if you’ve gone too far in thinning. If you’re overbuilding, then the thinning and bracing work that you are considering might be nullified or overshadowed by the fact that the structure is still too stiff. Or maybe the part that you’ve thinned will work fine, but the part that y ou haven’t thinned will be inhibited. But you won’t get 100% cooperation from such a top.

Third, you will probably produce minimally uneven tops no matter what you do; guitars in the real world always have something or other that’s not optimal.

Fourth, as with the example of water cited above, and if your gradient is not too unevenly made to begin with, then what you’ve constructed or misconstructed probably won’t matter. Or at least it won’t matter very much within the context of the flexibility of vibrational potential that the top has. The top will bend itself (sorry about the pun) to work in any way it can, to release its load of sound energy. It’ll modulate itself physically and vibrationally. As I said above, the vibrationally active areas of the top may functionally be a little bit asymmetrical, things may be a bit off-center, vibrational patterns might not be quite mirror-image, etc. But this is no big deal: the top plate has the capacity to function at least a little bit like that in order for the system — as it is physically constructed, with its unevenness and irregularities — to engage in an adequate monopole, cross-dipole, and long dipole. Finally, the sound will get out, sometimes because of, and sometimes in spite of, and sometimes without being much bothered one way or the other by, the work you’ve done. And I think this is where a bit of the magic comes in.

I hope this makes some sense.

F.A.Q.#5: Soundholes and Bracing Patterns

December 18, 2011

Q: If the soundhole is not in the traditional location at the end of the fretboard, is there a better bracing pattern than the X-brace, in your experience?

A: The soundhole is where it is, as a matter of tradition rather than critical thought: it’s always been put there. One might put this in terms of history trumping dynamics. History and tradition notwithstanding, the guitar soundhole has a tonal role to play, and I devote an entire chapter of The Responsive Guitar to the mechanical and dynamic functions of the soundhole with respect to brace location.

As far as the mechanical dynamics go, the soundhole in the Spanish guitar is outside of the main vibrating area of the face; it’s isolated from it by a massive brace that acts like a dam, and the comparatively delicate fan bracing on the other side of it does its work without being affected by exactly where, above that dam, the soundhole is. In the steel string guitar, instead, the soundhole is inside the main vibrating area of the face. It represents a mechanical perforation of that plate — and it necessarily weakens it. Imagine a drum head (a vibrating diaphragm) with a great big hole in it, and you’ll be able to grasp one of the principal bad dynamic ideas in the steel string guitar.

As far as bracing placement is concerned, my opinion is that the acoustical work of the bracing is more important than the specific location of the soundhole, and that these shouldn’t be in conflict with one another; therefore, I think there’s more to be said for moving the soundhole “out of the way” than moving the bracing around. Those kinds of judgments depend, of course, on understanding the functions and possibilities of various bracing systems. You don’t just want to move stuff around randomly.

Speaking of tradition vs. critical thought, the Kasha guitars (with the innovative Kasha bracing) were the first ones to focus on the bracing layout first and the soundhole placement second — in spite of how oddball those guitars looked. I give the Kasha people credit for understanding about putting the soundhole in a place where it helps rather than hinders. The soundhole’s dynamic function is to act as a port (as per the discoveries of 18th century Dutch scientist Christian Huygens, which I go into in my book), and as such doesn’t HAVE to be in any particular location. I recommend reading my book if you haven’t already.

Whether or not one moves the soundhole, it’s useful to have an idea of what each bracing layout can do, in terms of its mechanical and vibrational possibilities. Or impossibilities. There’s a logic to each bracing pattern and each one can be tweaked and altered in many ways — some subtly, some radically. And, as I said, part of the challenge is to not put the soundhole where it’ll create a problem. Either way, we’d have to understand how these factors interact before going on to talk about “better” or “worse”… because there are many ways to spoil the efficacy of any blueprint pattern and there are many ways to “get it right”.

But, let’s get back to your question about “X” bracing and soundhole location. The virtue of “X” bracing is that it ties the face together so as to create the possibility of a dominant monopole motion. Now, it won’t work nearly optimally well if the bracing/top are overbuilt and too stiff, or if the plate isn’t properly or consistently tapered, etc., and your job is to learn to do an INFORMED balancing act. Plus, the soundhole is right in the middle of this, sort of like interrupted ceiling beams that are holding up a roof that itself has a great big hole in it.

If you can get comfortable with the idea of relocating the soundhole to somewhere else then you do have to think about what to do with its area of topwood that is newly available as vibrating diaphragm. I mean, you’re creating an empty space bigger than any other empty space on that braced top. You could close the “X” brace up a bit… but that would necessarily open up the bass and treble quadrants, and you’d have to figure out if you were comfortable with that. As I said, it’s all a balancing act. If you didn’t want to mess with the balancing act then you might think about installing one or more finger braces into that space, to tie it into the rest of the bracing. I don’t have a better specific answer for you than this.

My unspecific answer is to think of what your changes might signify in terms of the main modal movements of the top: the monopole, the cross-dipole, and the long-dipole. Mainly, “X” bracing is a recipe for bringing out the monopole; it ties everything together. Fan bracing is a recipe for facilitating cross-dipole; there’s nothing there to prevent or inhibit that mode. Ladder bracing is a recipe for emphasizing long-dipole; it destroys the monopole and the cross-dipole.

So, if you were thinking of closing in the angle of the “X”, you would be justified in suspecting that this will facilitate more cross-dipole: the legs of the “X” would be stiffening the plate in a different way, as a function of their new orientation. So, the equation might look like: (Take away soundhole) + (closing in the “X”) = (more cross dipole). A second equation might be: (remove soundhole and add a bit more topwood) + (leave “X” the same) = (maybe a bit more monopole). Another equation might be: (remove soundhole) + (enlarge the space by spreading the “X” legs out) + (make new bracing accommodations to reinforce this larger space) = (?).

My point is that if you can accept that there’s some actually useful information contained in technical jargon such as “monopole”, “cross-dipole”, and “long-dipole” (which are simply formal words for some basic concepts of top vibration, and hence sound) then I think you can begin to have really interesting ideas about how to problem-solve your next guitar project, and make it better.