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So I talked to Roger for a bit an hour or so ago. I asked about two issues and asked Graham's questions as well. First I wanted to know about tuning the braces to specific notes. What he said, in a nut shell, is that the braces need to be tuned to a note in what ever chromatic scale you are using, mostly in the past 25 years that has been A440. It doesn't matter what that note is just as long as the note is part of A440 tuning. This is a delicate process involving finessing the final shape of each brace a little bit at a time as the work on one brace will affect the next. He has a table of all of the A440 frequencies free for download on his website but I tried and it didn't load up right for me, I can fix it but I need time to copy a bunch of the info to a new sheet.

Second I asked about tuning the 'box' as far as aperature size goes. Again, this tuning is directed towards the a frequency in the A440 scale and each box size will be a bit different, I think he said that a dread is 'G'. This is accomplished by altering the soundhole size once the guitar is complete. Completed these steps will maximize the volume and create better sustain and balance across all strings. So this, along with Dave Whites suggestion to tap along each brace to make sure there are no dead spots (he agrees with you Dave but says to then make sure that that note is in the chromatic to eliminate that 'wobble' you hear in out of tune harmonics) find the note and tune the brace.

Graham, he agrees, can't tune the box until it is together. On the second point, he is talking sharp or flat of the A440 note you are trying to tune to, so if you have a B flat, make sure you get B flat and not a couple of 1/1000 of a semi tone off of that, just like tuning your guitar with harmonics.

Scott and Kevin, your input is great and very much appreciated as well Alan always keeps me thinking, sometimes it even hurts! What I am trying to figure out here is what I need to do to maximize the quality of sound from my intruments (and share this with others). I am on my first guitar so some will say just build some first and then come ask, but hey, I push myself right from the start. Scott, you may not be prepared to do this but your work is very well respected and if you were tell use some things we could do to maximize the sound qualities in our instruments, we would all be greatful! These may be your trade secrets and I appreciate and respect that you may want to keep them, but if you are willing...

One more note (sorry for the pun..) of interest. Llyod Loar built his famous F5 Mandolins to C256, which was the norm then. Using A440 would now put C at 261.63 about a full 1/4 tone away from current C, wold make the mando sound slightly out of tune when played with instruments built to A440. He also stated that there are some that want to change A to 444 or 445. So you might see a switch in what Roger called 'Concert Pitch' again. that is the reason I just ordered a Peterson 490 tuner, you can program the concert pitch appearantly!

Thanks

Shane

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Canada

[QUOTE=Shane Neifer]   So this, along with Dave Whites suggestion to tap along each brace to make sure there are no dead spots (he agrees with you Dave but says to then make sure that that note is in the chromatic to eliminate that 'wobble' you hear in out of tune harmonics) find the note and tune the brace.

[/QUOTE]

Shane,

Thanks for this comprehensive feedback (no pun intended ... well only a little one ) from your conversation with Roger. All very interesting stuff and more grist to the mill.

The one problem I have with the above quote is just which part of the brace am I tuning? I'm pretty sure (I'll monitor more closely on the next top I brace) that the ringing notes I hear change pitch as I move along the brace - biggest extreme would be an X brace going from upper bout across the centre to the lower bout. I'm just listening and adjusting the shape to keep the ringing going.

My biggest influnce in the way I do my bracing "voicing" has been Scott Van Linge who has been very helpful to me - and I'm glad to see him posting on the OLF. I still can't "feel" all of the string patterns on the top as he describes and don't (at least yet) fully buy into the full circles as he describes, but his theories on brace and top balance under string tenion make a lot of sense to me together with flowing brace shapes rather than abrupt changes. I have certainly found to be true what he has said again and again, that very small (almost inperceptible) bumps gave a big impact when you find and remove them with very little sanding scrapimg. One example could be Greg G's posting of the big change in sound when he capped the X brace of his guitar.

The more I build the less I find I know "absolutely" and the more I am willing - and look forward to being surprised. That's what I love about guitar making!!

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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

You are right Dave, this is the intrigue! When I talked to him I talked specifiaclly about the cross and when I addressed this referred to each leg of the cross, I just assumed that they would be handled as seperate components as I think you need an uniturrpted length to get a handle on any changes. Roger was also quick to say that these are not his wisdom snad discoveries but are from the likes Dr.Kasha and his work at the Gibson factories. I feel taht Kevin's statement about tuned by design has some merrit and will get teh guitar in the 'range' but haveing the ability, should I say luxury!, to 'fine tune' each instrument gives hand builders that edge over factory built guitars. For me, it is the pursuit on a journey I hope never to find an end too.

Shane

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Canada

Shane,

I actually feel I've given quite a bit away already in the discussions on my web site, and in two articles published in GAL's "American Lutherie", in #47, summer 1996, and #66, spring 2001. I am currently writing an article describing work on a classical guitar, and how my theory applies to their different bracing patterns, which I hope to have published in the spring issue.

I will be offering workshops here in southwest New Mexico for luthiers who want to bring a guitar and have me show what reshaping braces can do as I go through the guitar to bring out its full potential and balance. This could include taking out and replacing braces, or adding new ones. I've done it on my own guitars if I find the need to correct an experiment that didn't work as planned.

Dave,

Hello again. The only full circles on a steel string are the first three strings, sometimes, just two. The low three only have an arc across the lower bout, and upper bout a bit. Check out the "Sound is Round" drawing on my web site. Wait 'til we get T shirts!!

Scott

Thank you Scott...I too used parabolic bracing based on info I received from you. Guitar sounds super by the way , first one too!

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Gwaltney Guitars

Thanks Scott, I will go and have a good look.

Shane

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Canada

Not to spark a controversy, but Cumpiano's thoughts are always interesting:
Cumpiano on Siminoff and tap-tuning

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

Interesting read Laurent.

I have great respect for Cumpiano since I'm learning to build guitars from his book, but I don't think most people who use tap tuning think with that one skill alone they will be able to make great guitars. I think that it's just one more tool/skill that can help get you there.

Thanks,

Laurent,

    I agree that Bill's comments and thoughte arer always interesting and worth checking out. I've read the Cumpiano book only after i'd already built more tha 100 guitars and found that much of it wasn;t applicable for me even if I'd read it before my very first instrument. I've never seen one of Bill's guitars nor have I ever heard anything from aplayer who has about their quality or tone so I can't draw any concusions from proof in any pudding whwn t comes to his actual abilities in building even though he's proven himself able to write a very thick book on buildng and market it. I fall much closer to the ideas of Siminoff although not completely in his camp on some fronts.

   The "skill" of tap tuning a top is more in the ear than in the hands and doesn't come with the simple ability to skillfully wield a chisel, but instead, from continuous exposure to more and more tops as the guitars are being built and the effects presented by the dimension changes made from one to another on their respective guitars as far as tone is concerned. You can't effectively tune the body cavity after it is closed since you can't gain clear acces to all surfaces on all of the braces in order to tweak the response and tone of the top or back themselves. Working through a 3.875" or 4 inch soundhole just doesn't give easy enough access. You can tweak certain facets of the tone and dynamic capabilities using those "through the soundhole" techniques, though.

   Remembe that tunign a top or back as free plates is simply a part of the process of achievng a final frequency for the body when it is closed and bound. Neithr will display the frequency that is the target frequency for the completed body, but after alot of tops and backs and being able to document the frequencies and charachteristics that the bodies with them exhibit, you can't help but to get familiar with their contributions and more able to predict that outcome before it is a reality. This makes perfect sense to me, but that may be something I may not want to admit...in public anyway. I hope it helps to pull the blinds back a little for some here.

   I disagree with Bill on his idea of shaping braces until they look right and not sound right since the paramount goal of any luthier isn't the appearance of the guitar, but the sound of it. We like them to look great, but it's even better when they look great and sound great...any player would agree, I'm sure.

There's a real trend in the guitar building industry and community for luthiers to do whatever is necessary to make their guitars as appealing as possible to the players...even to make comments and reference about other builders and their guitars that can create doubt in their quality for the potential customers. I've experienced even though I go above and beyond to compliment other builders and their work. I've made it a practice to encourage other builders in any way possible, but that favor is not always common to all builders when tlking about others' work and expecially when not in the company of the buuilder being discussed.

    Don't believe everything you here when it comes from a builder or from a loyal customer of any builder, but shop with your ears for tone that suits you and not what others say is great or rightfor you. Shop for tone and not for logos is a way to better put it. If my guitar is the right guitar for a particular player, I hope he ends up with one, but if another builder's is, then I'll hope that that's where he ends up. I've sent people who have come to me to possibly an order to builders that i thought would better address the guitar needs that they expressed rather than use them as a guinea pig for a new design just to get a commission.

Regards,
Kevin Gallagher/Omega Guitars

I was at Cumpiano's shop in March of last year and we had thaht very discussion. I agree with what he says at the end and it was the conclusion of our conversation on the topic. My builders use many different ways to arrive at the point they desire, a quality sounding, playing and looking guitar. As he pointe out, it is the maker taht is TUNED (trained) and you learn what works for you to make that the guitars you want. For me, it continues to be search for the path to this. Cumpiano does not tap, he was clear about that.

Shane

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Canada

[QUOTE=Kevin Gallagher]I've read the Cumpiano book only after i'd
already built more tha 100 guitars and found that much of it wasn't
applicable for me even if I'd read it before my very first instrument.[/
QUOTE]

I built only one guitar so far last fall -and want to do more as I took
immense pleasure doing it-, and read Cumpiano's book shortly before I
started. Although very instructive and well organized, I didn't follow most
of his instructions and did thing very differently.
I think when he says "visually" about the braces he tries to find balance
between the most resonant top possible and structural integrity, and one
can devellop a good "eye" and "hand" to do so, depending on whatever
wood property is at hand, the tone envisionned and so on.
I have to admit that when I thinned my top and carved the top/back
braces, even though I could hear the effect of what I was doing when I
"tapped" the plates, the way it could translate into "real" guitar sound was
way too abstract. I ended up following my instincts and visual/tactile
clues, and it worked.
Chance? Perhaps.
I just find Cumpiano's "philosophy" appealing, I do not think there is
"one" system to do things, what he writes about other topics on his
website is also well worth the read.

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

Kevin Gallagher wrote:

[You can't effectively tune the body cavity after it is closed since you can't gain clear acces to all surfaces on all of the braces in order to tweak the response and tone of the top or back themselves. Working through a 3.875" or 4 inch soundhole just doesn't give easy enough access. You can tweak certain facets of the tone and dynamic capabilities using those "through the soundhole" techniques, though.]

I have to disagree with this statement, as I have been doing just that in my revoicing work. It is a challenge to reach certain braces down deep in the box, but it can be done with special sanding blocks and tools I have developed since I began tweaking braces in 1983.

I have been exploring tapping the arms and legs of the X brace at equal distances from its crossing point. An assumption is that the tap pitch should be the same on each side of the arms or legs for balanced vibration. A lower pitch ususally means more mass, although I am still scratching my head over some subtleties in cross sectional shape and taper that also influence pitch, and the release of the strings' energy into the top. When the balance is close, a few strokes of sandpaper can change one side from lower to higher pitch.

There is also a resonance between the arms and the legs that can add or detract from volume at the bass end, especially, as they "bounce" together. Harmonics, as well, are influenced by the interplay. If and/or when I figure this out completely, I may be able to explain it even to myself. For now, it's trial, smoke and blue lights.

Scott

I’d like to thank every one of you for adding to this discussion. It would seem it is the differences in which we all do things that bring richness and intrigue to this subject of tuning plates, body and braces etc. It also seems healthy to remain skeptical of “one system” that is exclusive in providing a successful instrument build.
It is important for those of us who have not built 100 guitars yet, to choose some method to fallow in this case. I am grateful that so many of you folks are willing to share your findings and insights.
Until the day when I have made enough instruments to form an educated opinion, I will be relying on the discussions here.
Thanks again,

Wade

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

Scott,
I appreciate that you can get deep into the body to hit alot of the more distant bracing, but I know that it's very difficult to emulate the strokes of a chisel thrugh the soundhole and nearly impossible to hit it all. I've done some after market brace shaving for a few people in instances where the bracing was just obviously heavy on their tops.

I'm glad to hear you've had such great results for so longm though.

   I guess I should have said "as effectively" since you're obviously getting in there.

Personally... if it were me... I would haul myself out to Ervin Somogyi's class in February. After I saw him speak @ ASIA I definitely want to hear more about what he has to say and his technique.

Unfortunately... that is just not in the cards for me this year.....

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