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Lance@LuthiersForum.com

Oh and to post a link,

1) click the 4th button from the left (Blue globe with chain link)
2) type the NAME YOU want your like to say.
Example see Lances website HERE (I typed the word HERE)

3) click ok, then copy and paste the URL you want to point to into the box, click ok, all done.LanceK38819.3953703704

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Lance@LuthiersForum.com

I don't think you should do tap tuning INSTEAD of the four items that Cumpiano talks about. You should do the tap tuning in ADDITION to the four items. I also think that you should do Chladni patterns on the plates before gluing them to the rims. Any information that you can collect about the instrument may be useful in the future.

You may notice a pattern where a top tone of a certain character accompanied a guitar that sounded particularly nice. Then you try to adjust the braces and top to reproduce that tap tone and see if the resulting instrument has the sound you want. The same can be said about Chladni patterns. Patterns that look like THIS or THAT may correlate with certain characterists of resulting instrument. This may give you a degree of control over the result that building to a specification can't.

Any information that you have is better than information you don't have.

Having spent some time with Mr. Cumpiano in his shop, my impression is that he operates very much by feel and observation of wood etc. I don’t remember seeing sprinkle patterns and sound generators in his shop. When asked about it he said that one develops an understanding after 10 to 30 builds or so. Personally, I think using some systems of measurement along the way certainly can’t hurt the learning curve. Especially when it comes to the Top, bracing etc..

Mike, Do you think the information you get from using the Chladni patterns system is repeatable enough to “pool” that information to make it useful for all.
Is there a certain amount of standardizing of equipment or technique that has to be in place?


Wade

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Wade
Nashua, NH
http://www.wadefx.com

Hesh, I had this very discussion with Bill in his shop just over a year ago. What we agreed after this discussion is that it is difficult to predict the final sound of your guitar by tap tuning a top. There are so many other variables involved. There have been some very good work on using other methods for maintianing predictability in your work, I have Siminoff's "A Luthier's Handbook" and Hurd's "Left Brain Luthiery". I have also talked with both of these guys about predictabilty.

At the end of teh day:

Cumpiano uses wood selection as his first criteria, he wants to see little runout and a high medullary ray display (indicating that the wood is well quartered), next he wants the top quite stiff but not too stiff.

Siminoff suggests taking measurements as you go and record your successes. The measurements are typically deflection of the plates. Once you have what you like then repeat it. This means a less stiff top will be left thicker than a stiff top but when you are done the deflection should be the same.

I only recently acquired Hurd's book and talked to him for a little bit. His thinking is along the same lines as Siminoff (I think) but offers more supporting data (I think).

Still, I like Al Carruth's caveat..."If it looks a guitar, it will probably sound like a guitar". Beyond that you are just tweaking to get the details (that is the fun...and stressful...part!)

Oh ya, my statements above are just my interpretation of the conversations I have had with these guys and should not be taken to necessarily accurately respresent thier much more knowledgeable thoughts on these issues. They are far more qualified to speak on these issues that I ever will be! I remain a lowly tonewood producer guitarmaker wanna be!

Shane

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Canada

I tap on my tops, and backs to hear the differences from one to the other, but tap tuning? My personal opinion is that it's akin to snake oil. Something devised years ago to snow laypersons, and the joke goes on.....

Al

Sorry guys, i just wanted to try Lance's way of copying a link!

here

Thanks Lance!Serge Poirier38819.5481712963

Interesting points made by Cumpiano, i too am a feeler of wood first, makes perfect sense to get to know what you're about to be building with.

Hey Hesh,

Siminoff is also one of my customers and I have talked with him a few times. I think that Roger is trying to to find some means to 'measure' repeatability. And there are others that are trying to do that also. With experience, Cumpiano and I both agree, you do begin to 'measure' but it is just difficult to explain what that process because it becomes much like "there, that is what I was looking for". Defining "that" is the hard part but you know what it is with experience. Siminoff leans more in the science camp and Cumpiano leans more in the subjective camp, in my humble estimation. For me, I read as much as I can about methods and just keep lots of notes as I go.

As for training, Cunpiano still builds in the same method as in the book, with a work board and bending by hand. No moulds and no forms. So if that is the way you want to build and get some experience then he is the guy, low tech hand built. If you want to use side benders and build in moulds, even from your own designs, then you may want to consider training with someone who builds that way. Bill is a great guy with a huge wealth of experience and information but there are a lot of makers out that there that teach with the same qualifications. Oh ya, except that Cumpiano might have a couple of our fret slotting blades and a few Lutz tops .

Good Luck!

ShaneShane Neifer38819.5640972222

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Canada

First I'll say that I will go whole heartedly with 1 and 4 on the list, by taking 2/3 we assume that these elements are evoloved to their ultimate design, on the thicknessing one we assume that all tops that we select are equal, which I don't believe to be the case, I would also argue that information in this area that is old is potentially misleading as we just don't have that much access to the same quality of timber they had years ago (Thinking true German Spruce).

On Tap tuning I am a believer, I think it is totally true that it is difficult to predict the final result in absolute terms just from tap tuning, it can work as a good guide. Two examples take two tops braced from similiar stock and using comparable tops, tune them the same, and with all other elements equal you should produce two equivelant guitars.

Second example I had a customer who wanted a guitar for playing with pipes and wanted rich bass for this purpose so during tap tuning I aimed to tune the top a step lower than I normally would, the result was a rich bass, now one could argue that I simply made the top more flexible and thats true, but what I am getting at is I used Tap Tuning to guide me as to how flexible.

As for why it works, frankly I don't know and don't care, not very scientific I guess. I should also add I am not holding this up as the holly grail, only what works for me.

[QUOTE=Hesh1956] We need to hear from some more tap tuners besides Mike who can expound the virtues of thumping wood.[/QUOTE]

Hesh,

It depends what you mean by "tuning". For sure all of the things that BC lists are an integral part of the whole build and end result, but tapping around the top as you profile and shape braces puts you in a good "communication" with the top wood and is like the "icng on the cake" in terms of small final adjustments. I've described my process before. I suspect what I'm doing is a rough "audio" equivalent of Mike's Chaldini patterns. Using this process has definitely moved me into the beginning ballpark of "great" sounding guitars rather than good guitars, and I am getting more confident in predicting the response of the guitar when the strings go on. Then again it could just be the natural learning curve after making 20+ guitars.

By the way, some of the wildest looking tops produce fantastic sound, but probably still fits BC's criteria (apart from the perfect quartersawn one).

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

Where's Mario?

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now known around here as Pat Foster
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http://www.patfosterguitars.com

I'm inclined to agree with Dave.

Of course, the selection of good woods is critical, as is going with a bracing design that will give predictably good results, etc. But I've had at least one instance in which I copied the bracing design, down to height, thickness and material, as well as the top wood and its thickness, of a very well known classical builder and found that the top's pitch was way too high. I knew from experience that it would result in a quiet, thin sounding guitar, so I shaved down the braces until the top tapped at a pitch closer to what I prefer. In retrospect, I should have shaved the braces down even further, since the guitar was a bit thin and quiet sounding when I first strung it up. But it has opened up nicely since then. The client tells me that the sound is continuing to improve, but I still think it would have been even better if I would have listened to my ear and not my eyes, and shaved off even more.

Also, I've found that probably the most popular classical pattern -- the 7-fan Torres pattern -- often requires adjustments to the top after the guitar has been completed. It is not unusual for guitars I've built using the Torres 7-fan pattern to require a bit of adjustment (as in removing small amounts of wood from the underside of the soundboard or braces) to improve the overall balance of the instrument. I'm not good enough at this to be able to tell where these problem areas are before stringing the guitar up, much less before the top has been attached.

Best,

Michael

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Live to Play, Play to Live

I just throw the glued up assembly in the Koi pond if it floats its getar

and if it sinks its a witch

I wanted to see if anyone would pick-up on the second line    way to go Russell

[QUOTE=RussellR] and if it sinks its a witch [/QUOTE]

That's funny...   

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

I think the objective of tap tuning is not necessarily the single goal of making a "great guitar" it is the process of getting predictable and repeatable results.

Clearly this is the great mystery of what we do. I am increasingly convinced that regardless of what camp you are in: science -- where you measure everything and use data to try to predict results, or "art" where you tap, listen, tap, listen etc. I think at the end of the day the really really really significant variable that determines proficency is ** experience **. Both approaches seem to yeild decent results but you need to have a (reasonably) sizable base of experience with your approach.

Again, not to say that your early guitars can't be very good, but I suspect that without a decent base of experience controlling or predicting the outcome will be very difficult.

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

Testing a web link
SERGE!!!!!!
SERGE!!!!! SERGE!!!!

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

Which ones Serge

Andy!

first one Russ!