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Was wondering what experiences you guys have had relative to before and after results from the tap-tones, before construction, to the resulting sound after construction. Do you find that a better(subjective of course) sounding piece of wood, either top or back, before construction leads to a better sounding guitar? I ask because I have a set of Cocobolo and an EIR set that sound very different after bracing, the EIR sounds "better" so I am wondering if I should expect a better sounding guitar....assuming everything else were the same. Your experiences would be greatly appreciated. Same question could apply to tops as well, the two tops I'm working with now are very similar in tones at this point.

Thanks,
Greg

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Gwaltney Guitars

Greg

Now thats a very good question, in the first instance you there is no single tone you would expect all woods to have as each species will be differnet by nature and density.

I would say at best the Tap tone of a Top before it is braced, thicknessed etc, is an indicator.

How do you define better?

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Jim Watts
http://jameswattsguitars.com

This is a fascinating question.

I haven't built nearly as many guitars as a lot of people here, and I have focused on dreads, but here's the opinion I have formed based on those I have built. I have used a fair variety of woods, with significantly different tap tones, and they all sounded very different when first strung up. But after they each had a chance to break in, they sounded surprisingly similar.

There are differences. My Sitka/EIR dread is a bit louder and boomier than my Englemann/Cocobolo dread. The padauk/Englemannn dread is a very tiny hair brighter than the Englemann/Cocobolo dread, but you really have to pay attention to notice it.

Bottom line, they all sound great, and they don't sound as different as you would expect. I conclude that wood influences tone a little, but for the most part the sound of my guitars seems to be determined by the way I put it all together rather than the choices of materials.

I'm anxious to hear others' thoughts.

   I think that so many things come into consideration that tap tone alone won't guarantee a good sounding guitar. The bracing, stock stiffness, basically every aspect of the build will affect the tone.   After maybe 20-30 builds (maybe more maybe less) one might be able to guess at certain characteristics in the sound, but even then...

   Like Jim say's, how would you define better? It's all subjective.

   Pre-build, I think you can determine that a board is stiff and you can see how long it 'decays' after being struck, but that's about it. It might suggest potential but not absolute success. Just my opinion. Cheers.

AlainAlain Desforges38793.597974537

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I'd like to be able to prove, just for once, that money wouldn't make me happy...

In a raw un-joined plank I look for pleasing and sustained ring with complex overtones but no specific note. When voicing I shoot for a clear dominate tone with good sustain. It is hard to say just what note I look for as I don’t really shoot for a specific note, but rather a clear dominate note. I have read where others voice toward G# and that is probably a common general range for spruce. But I am not very sophisticated in my voicing technique. I go by what is pleasing to my ear. With only 30 builds and probably 10 different species and at varying stiffness it would be impossible to say this is what I do because each top has been different.

I've always found discussions of 'tap tones' to be confusing. As has been asked: what's 'better'? Some people shave braces until the 'fundamental goes away', but what does that mean: the fudamental is defined as the lowest resonant frequency, and there's _always_ going to be a lowest resonant frequency! One person's 'clear ring' might be somebody else's 'lack of complexity'.

In the end, the only ways to learn about tap tones are to either work out some system for yourself, or get somebody who's good at it to teach you their system. In terms of the physics involved everything can change depending on where you hold and tap and listen, so you have to standardize on one method and then work out what that means.

I use a sort of 'technoid' version of tap tones; 'Chladni patterns', often caled 'glitter patterns'. It requires a bit of equipment to use, but has the real advantage of providing numbers for resonant frequencies and patterns of movement that can be compared directly. There are articles on how to do this. Once you know what those 'glitter' patterns are you've got some sort of handle on what you're hearing when you hold and tap.

My opinion, based on some fairly well controlled experiments (it's darn near impossible to do 'perfect' experiments, but you can get close) is that the _shapes_ of the patterns, and the clarity of the tap tones, is probably more important than the pitches of the tones. What I think works best is to get a certain 'balance' between the bracing and top stiffness, and a 'good' distribution of that stiffness, and this is evidenced by the shapes of the patterns and how clearly they sound out when you hold and tap appropriately.   

Buy good wood, thickness and brace well, glue it up and they all sound good. So much else is in play from the joined top or back through the entire process. I have noticed wide range and difference in woods, all tapped and created a tone, and all have sounded good when played after completion, maybe different, but still good.

Mike
White Oak, Texas

Well said Hesh,

Mike
White Oak, Texas

Yep, Our Hesh sounds better by the minute too!

Hi Hesh

I think you are right about the construction being the biggest influence, I think that was what I was trying to say but not as elequently.

When you tap tops certain ones ring like a bell and this can be a good indicator, that braced and tuned well they will have a fine sound, that said of course to make a comparison tops must have the same thickness and dimension and in my experience the same moisture content.

Stiffness is another good indicator, but that said on my smaller guitars I deliberately choose tops that are not so stiff as I think this gives a small bodied guitar a little more get up and go.

When I am tuning I look for an even and for lack of better description a musical ring to all areas of the top, like hesh I'm not looking for a specific note.

Thanks Everyone,

Where do you tap on a braced top as your looking for the specific resonance that sounds good to your ear. Is it where the bridge will sit, or all over the top? Do you find that the top needs to be resonant, alive, ringing, whatever word works there, all over, or just in a small zone?

I have noticed from just one build, seems like ten, as I have sanded here and there way too much, but, I have learned that every little detail makes a difference in the sound.

Greg

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Gwaltney Guitars

I do things a little differently maybe.

I use a two part system first I tap along the path of all the braces and look to eliminate any dead spots ( The credit for this goes to Dave White as he showed me his method which is similiar).

The second part I won't put up in the open forum, for fear of opening back up old arguments, but I would be happy to share vis email or pm.