Bamburg build for Healdsburg

[JBam]

Cocobolo back. More pics to come.

[JBam]

[marty bradbury]

Looks great!! What is the stuff you sprinkle on the top and why?? Always been curious about that.

[ZekeM]

Originally Posted by marty bradbury

Looks great!! What is the stuff you sprinkle on the top and why?? Always been curious about that.

That is magic dust made from the horns of unicorns. It make the tops magically come to life

Really though it's for chladni testing to adjust bracing and such to get the "tone" correct for a good sounding guitar. It's a lot of math and stuff that I don't really understand but perhaps someone that has studied it more will say some about it.

[JBam]

I don't know about the magic but I keep hoping. For what it's worth this ring is at 248 Hz. Perhaps if Al Carruth stops by this thread he would comment more articulately than I.

I do have target frequencies I am going for at specified patterns. I believe this has made my building much more consistent.

[ZekeM]

I've been wanting to learn more about this just for the reason you said "consistency". I don't expect to understand it all or grasp how it all works but I would like to find something that sounds good and have a way of testing for repeating the process. Did you learn from the gore/gilet books? Or do you have any books you would recommend to learn this stuff?

[JBam]

Like most luthiers, this is a life long learning process for me. I read everything I can find and love to talk to other builders at the shows.

Two sources that have been very helpful are: "The Art of Tap Tuning" (book) by Roger Siminoff and the DVD "Free plate tuning with Alan Carruth."

These are good starting points to begin experimenting. I do not look at "plate tuning" as the fool proof formula for a great guitar, but simply as another tool in the bag. The more tools the better, right?

[ZekeM]

Absolutely correct! I'll have to look into those sources. I'm still new to the lutherie game but I'm trying to get a good process down as quickly as possible for consistent results.

[Steve Kinnaird]

Really handsome Coco, Jeff. Look forward to seeing the finished product.

Steve

[JBam]

[IMG][/IMG]

[justonwo]

Really lovely Cocobolo. Looks like a great build.

[DOrion]

I have had the pleasure of meeting Jeff in person and visiting his shop for the first time in May. I have to tell you, his guitars are stunning and you can see the love of his craft in his detail to get it right and to get that "Bamburg" sound and look consistent with every instrument.He definitely has a vision to set his guitars apart in quality build and sound and I think he is well on his way to becoming one of the nations top builders. The guitar he is creating in this series of posts just might not make it to Healdsburg...it might be found at my place if I'm lucky!

[robj144]

Originally Posted by ZekeM

I've been wanting to learn more about this just for the reason you said "consistency". I don't expect to understand it all or grasp how it all works but I would like to find something that sounds good and have a way of testing for repeating the process. Did you learn from the gore/gilet books? Or do you have any books you would recommend to learn this stuff?

I'm not on expert on Chadlni patterns for luthiery, but I do know how it works from a physics point of view. Any two dimensional plate, like a guitar or drum head for instance, will have certain standing waves. The easier one dimensional analog is a guitar string. The standing waves on a string is the origin of the harmonics. Basically for each harmonic and corresponding frequency of the standing wave for a string, there are nodes where the string appears not to move and anti-nodes where it moves the most. For two dimensional objects, the standing waves associated with each harmonic is much more complicated. It can be easily calculated, as it as for strings, for symmetrical objects such as circles, rectangles, and squares. For a complicated shape, like a guitar top, it can be calculated numerically by a program. However, it is much easier to determine by simply spreading graphite dust on the top and driving the top with a defined frequency. The anti-nodes, where the top is moving the most, shakes the dust to the nodes, where the top is not moving. This, for a particular frequency of standing wave, the complicated standing wave pattern can be determined.

It's best demonstrated on this rectangular sheet driven by a speaker:

http://www.youtube.com/watch?v=wMIvAsZvBiw

I'm a physics instructor and teach this (standing waves) by the way.

[DOrion]

I just noticed that Jeff Bamburg is highlighted in this months issue of "Acoustic Guitar" magazine and also a video review on their site under "Shoptalk".

[corbetta]

Jeff, that looks great. Is it a candidate for the demo slot on Friday?