Tap tones: my take

 Dear William,

Of all the areas within guitar making, the one issue I find difficult to learn about is tuning the soundboard, both during thicknessing and during brace scalloping. I have read many books, including your excellent book, but have not be able to find anything that gives me the basics of this all important step. If this could be covered in one of your Newsletters, I am sure it would be greatly appreciated by all. As I work in complete isolation and have no guitar makers to disucess this with, my only hope is to gain some insight through the generosity of makers such as you.

J.E. Perth, Western Australia

You heard it here first: "Tap-tuning" has been oversold. Let's put it into perspective.

When I was learning how to make guitarsI went through ust what you're going through: I had heard about something called tap tuning and was just as mystified and eager to learn about it. I presumed that it must be the secret for attaining consistent, replicable, world-class results. I thought it was like an act of wizardy that only a select and most sensitive artisans could command—and that they were unlikely to readily disclose the skill to me, so I would somehow have to learn it myself.

Builders, alas, often do things on guitars which they really can't explain— but they do it because they were taught to do it, and they're afraid if they stopped doing it, the nice sounds they usually get will go away. So they keep doing it. Then, when you ask them why they do it, they are all too happy to just make up vague, fanciful, jargon-laden accounts which will leave an impression that they know exactly why they're doing it in minute detail, and by implication demonstrate that they can somehow successfully manipulate all these invisible sonic phenomena on the guitar with ease. Luthiers usually won't stop you from believing that they are wizards. This is most painfully obvious in the realm of "tap tones."

Yes, you may "tap" a top to derive some rudimentary information about its anatomy. What you hear does give you some feedback clues which is useful and helpful. The "tuning" part is what is so misleading to beginners. At some point (most often toward the end of the process) many builders attempt to make some final changes in the anatomy of the soundbox, which the builder believes (I've selected this word carefully:) believes is exercising some control over the final results. Both, skillful experts and deluded fools, equally, scrape here and there, tap, press, reach inside, remove a little on the back braces, on the top braces, and then at some point say THERE. It's just right.

Then there are other builders, masterful experts and deluded fools alike that DON'T. They believe that they're making all the crucial decisions in the INITIAL stages of the construction: materials selection, materials dimensioning, design: that is all they need to achieve the desired results.

My good friend and colleague, Alan Chapman is confident that he has come to appreciate the difference of fine changes in bracing heights, soundboard thickness, patterns, and has come to BELIEVE that he can goose the sound quality of a certain note, or smooth out, or sweeten, or balance, or adjust the performance of distinct notes and distinct regions of the fingerboard by subtle changes in specific areas of the soundboard. With all respect to my dear friend, Alan, I believe that this is delusional. The soundboard is responsible for the production of a very limited part of the entire guitar sound spectrum. Yet his results are terrific. So I have to swallow a good portion of my skepticism when it comes to Alan's guitars. Yet, I know of other makers whos results are equally phenomenal that do NONE of that.

That is why I say now, like I said fifteen years ago in my book, that "tuning" is something that can't be taught but can be learned. This means that over time, each maker devises a series of actions which conform to a refined mental model that they've derived of how the guitar functions. This happens as a result of making, thinking, worrying, fussing, cursing, tossing and turning, eating and sleeping guitars for years and years. The mental model becomes more and more refined, and more and more PERSONAL. Jimmy D'Aquisto lectured that he made oval soundholes in his acoustic guitars, so the sound would "squirt further" like water from a similarly-constricted hose nozzle. The audience snickered when he said that. But nobody in the audience was getting $22,000 per guitar like he was. Snicker at that.

The upshot is that luthiers make excruciatingly poor sources of information on instrument acoustics. If you ask them about how they make their guitars work the way the do, and how WELL they work the way you do, I guarantee you, you will get an earful of useless mumbo jumbo. DONT ASK LUTHIERS QUESTIONS ABOUT INSTRUMENT ACOUSTICS, i.e., that if they "tune" the soundboard to G# that the "sound" improves. You'll then "tune" the top to G# and you'll never know if the sound improved for doing that, or by doing something that you didn't realize you had done, like select a stiffer top or denser neck wood, or making the bridge a little wider or fatter.