Best Little Guitar Festival in Texas

Aaron in the Booth at the Brownsville Guitar Ensemble Festival 2012

Aaron and I just got back from a trip to the University of Texas at Brownsville.  We were there as a vendor at the Brownsville Guitar Ensemble Festival and Competition showing five of Aaron’s classical guitars.  Aaron is a luthier who builds hand crafted guitars for his company Wood Ring Guitars.

This is not the only guitar festival we have been to this year.  There are several classical guitar festivals that occur around Texas every year.  Many are centered around university guitar programs.  Many of the major universities in Texas and several community colleges and high schools and even some elementary schools now have classical guitar programs who are taught by a group of very talented guitarists.  This is resulting in more and more people being introduced to the classical guitar and the amazing music written for it.  The quality of the competition and the performances at all of these festivals is outstanding and every year the crowds get larger and larger in response to this.

I think of all the festivals I have been to in the past couple of years, I enjoyed the Brownsville festival the most.  This is not because the entertainment and quality of competition was not as good at the other festivals.  I favor the UTB festival because it is unique in that the competition is ensemble based rather than being individually based.  There is an amazing spirit that permeates this competition because the ensemble competition requires each group of individuals to focus on working together as a team rather than competing as individuals.  Dr. Michael Quantz is the head of the guitar program at UTB and he has created an elite classical guitar program that is affecting the classical guitar scent throughout Texas and the Southwest in an extremely positive way.  I think many of the other university guitar program heads in the Southwest would agree with this, based on their growing participation at the yearly festival.

There is a 75 MPH speed limit between San Antonio and Corpus Christi.

The 75 MPH speed limit is nice when driving long stretches through Texas.

I have included quite a few photos from our trip from Wood Ring Guitar headquarters in Weatherford, Texas to UTB.  Aaron and I made the trip in one day, alternating in the driver’s seat every couple of hours.  This made it an easy drive.  We stayed at the Marriott Courtyard hotel which was recommended by the festival and we got a festival discount resulting in a nightly cost of $89.00 which was extremely reasonable for such a nice hotel. 



Guitar players practicing in the hot tub at the Hotel.

Once we settled in at the hotel and got all of our luggage and guitars squared away, we relaxed a bit and then we went to a local Japanese restaurant for dinner.  The sushi was fantastic, but we learned to never order Thai food at a Japenese restaurant.  We ordered Pad Thai, which is normally a very delicious Thai noodle dish.  Instead it tasted like an odd mixture of Thai Spiced noodles in a spaghetti sauce laced with mexican spices.  Not very good!  We also dodged a bullet that evening when we ordered sushi because we heard later that the spicy tuna roll at various sushi restaurants in the area caused a rash of food poisonings.

This is the entrance to the concert hall.

View of the Arts Center foyer from inside the Wood Ring Guitars booth.

The next day, we set up our booth at the new Arts Center at the university.  It is a beautiful building that has a gorgeous foyer and a wonderful concert hall that was acoustically tuned to perfection.   Our booth was in the foyer in front of the concert hall entrance.  Dr. Quantz and his staff met us as we entered the building to set up our booth and throughout the festival they were exceedingly helpful and made our gig at this festival extremely enjoyable.


Another view of the UTB Arts Center foyer where we set up the Wood Ring Guitars booth.

For the next three days, Aaron and I talked to more than a couple of hundred people interested in touching, holding, playing and talking about the Wood Ring Guitars that we brought.  It was a great experience for both of us.  We met and talked to many folks who, like us, love the guitar and all kinds of guitar music, especially classical guitar music.  We also were able to visit with many of our friends who teach guitar and who play professionally.  We also had the treat of being able to visit with members of two groups who headlined the entertainment for the last two nights of the festival.

On Friday night the Texas Guitar Quartet played.  It was an outstanding performance from four of the best professional classical guitarists on the Texas scene these days.  This performance was done in conjunction with the realease of their first CD which is named Red for the title song on the CD.  The entire concert was played beautifully.  On Saturday night members of the Los Angeles Guitar Quartet played an amazing concert.  I have seen these guys play several times in the past couple of years and they always amaze me with their virtuoso performances.  This concert was no exception.  It included a premier of a new piece written for a large guitar ensemble written by Shingo Fuji in honor of the victims of the 2011 Japan earthquake.  Mr. Fuji conducted the ensemble which included both LAGQ and the UTB Guitar Ensembles.  It was beautiful and moving to be sure.  The entire program was extremely entertaining and the guitar playing was impeccable.

We had the beach almost to ourselves.

We had the beach almost to ourselves. This is me walking along the shore.

It was not all work.  We work very hard at this.  Sometimes we end up working seven days a week.  Thus when we get an opportunity to travel for business purposes, I am a big believer in having a little enjoyment and down time during each trip to experience the culture of each place we visit.  We did not have much time, so for this trip, Aaron and I drove to South Padre Island to have breakfast on Pier 19 and then to walk on the beach to enjoy the sun and the smell of the ocean breezes for an hour or so.  It was great.


Brownsville area border patrol station.

Lots of cameras must have taken our picture as we proceeded toward the border patrol station.

After the festival, we drove back home.  About 30 miles North of Brownsville we were stopped at a Border Patrol checkpoint.  We were asked if we were citizens and then told we could go on, but not before about 30 or 40 cameras had taken our pictures to help them determine that we were ok.




Bluebonnets and Prickly Pear Cactus just south of Marble Falls.

The Blubonnets are absolutely beautiful along the Texas rural roads this year.

As we proceeded north of San Antonio we were able to photograph some of the millions of bluebonnets that are currently blooming.  This year they are exceptionally beautiful because there has been abundant rain.  It seems to me the beauty and abundance is enhanced because of the terrible draught that we had in Texas last year.  The contrast from last year was amazing.



Aaron and I had a great time.  It is really cool to be able make a living doing what you love to do.  Aaron has discovered that he has a real talent in designing and making these guitars.  I have a strong science background and I have helped him, by using the principles of physics and acoustics, to work out a guitar design that really sounds great.  Combined with Aaron’s amazing craftsmanship and his unique artistic and design skills, I believe we are beginning on a journey that is full of adventure and fun all the while offering some of the guitarists of the world with outstanding instruments to play.  What could be better than that?


The Craft of Guitar Lutherie – Strength in Numbers


The Next Two Wood Ring Classical Guitars to be Completed Before the End of 2011.

Aaron and I have been working very hard to finish two beautiful classical guitars that he has been building, side by side.  One has a  Western Red Cedar top with Cocobolo sides and back.  It has Bocote trim and a Spanish Cedar neck.  The other guitar has a German Spruce top with Indian Rosewood sides and back. It has Bloodwood trim and a Spanish Cedar neck. We have been working on these two guitars for over two months now.

Although much of this time was spent in crafting the two instruments from their component pieces of wood, a significant amount of time was spent performing extensive tests at every level of construction. Our goal in doing such thorough testing is to have a very thorough scientific understanding of every step in the process of building each classical guitar we produce.

 Although this testing and record keeping takes a lot of time and work, we believe it is well worth it for three reasons.


  1. We want to be absolutely sure that each Wood Ring Guitar is built to last a lifetime. This is done by applying both theoretical and empirical data to our building approach in order to make sure that the most vulnerable parts of the guitar are strong enough to endure decades of playing (strength testing).
  2. We want to be able to reliably reproduce the qualities that contribute to a great sounding guitar (acoustic testing).
  3. We want to continually improve the building process and the finished product from both an acoustic and artistic point of view (record keeping, feedback, and analysis).

Our aim is lofty but we feel strongly about it.  We are committed to creating instruments that will gain in value over time because of their unique artistic beauty, their outstanding sound qualities, and a look and feel that gives each owner that special feeling that only a select few instruments throughout the world can bestow upon them.

Today, I want to discuss the process we use to test the strength of our soundboards. This testing process is very important because:

  1. It allows us to fine tune the soundboard such that we are absolutely sure that each guitar is strong and built to last.
  2. It gives us feedback in fine tuning the top and bracing system such that we can obtain the optimum sound characteristics possible.
  3. It backs up our commitment that the guitar will sound as good or better 10, 20 or 30 years in the future as it does the day it is purchased.

 Sound Board Strength Testing

It is the soundboard that is responsible for most of the sound that eminates from a guitar. When the player plucks or strums the strings, they start vibrating. This vibration is transferred through the bridge and into the soundboard. For standard guitar tuning, frequencies from 82.407 Hz (Open 6th string – E2) to 880 Hz (17th fret on 1st string – A5) are generated. To achieve this, a lot of tension (both static and dynamic) is exerted by the strings onto the bridge and the soundboard. The tension exerted by each string depends on several variables including (a) active string length, (b) frequency of the string, and (c) mass per unit length of the string. For a classical guitar the total tension exerted by all six strings is approximately 85 – 95 lbs. of force.  Due to the way the strings are attached to the bridge, the force of this string tension applies a rotational torque on the bridge and soundboard with the front of the bridge pushing down on the area between the bridge and the soundhole and pulling up on the area between the bridge and the bottom edge of the guitar.

Torque Exerted by Strings on Bridge and Soundboard

As a general rule of thumb, the less mass there is in the soundboard and bracing, the louder and more responsive the instrument will be. Of course there is a limit to this and in reality a luthier must find a balance between the soundboard strength and the amount of mass that the soundboard will have. As mass is removed from the thickness of the soundboard plate and the thickness and height of the braces, the more the soundboard will deflect and warp in response to the tension placed on the bridge by the strings. This is good to a point and every classical and acoustic guitar top deflects a small amount downward between the bridge and soundhole and upward between the bridge and bottom of the guitar. As long as this deflection is kept within some well established design parameter guidelines this results in great sound and a very durable instrument. If this deflection exceeds these guidelines, then over time, the top will start to deform and cracks may appear around the bridge. Ultimately the soundboard may collapse. This effect can be magnified if the guitar is exposed to extreme conditions of varying temperature and humidity.

 Testing Apparatus and Procedure

As part of our testing process, we use a method of soundboard stiffness testing and deflection compliance that was first suggested by David Hurd in his book Left-Brain Lutherie – Using Physics and Engineering Concepts for Building Guitar Family Instruments. This is an outstanding book on the application of science and engineering to the craft of Lutherie. In this book, David proposes that deflection measurements of the soundboard be taken at the point in the building process where the soundboard has just been attached to the sides and the back has not been attached yet. This allows the lutheir to make both soundboard thickness adjustments and bracing height and thickness adjustments based on results of the deflection tests and Chladni pattern tests.  

The apparatus that we use for deflection measurement was hand made and is based on David’s Luthiers Forum series of articles which outline how to build the apparatus and how to use it. The apparatus is simple and is cheap to build.  It is a well thought out apparatus for measuring guitar top deflections. After we built it and calibrated it, we performed extensive testing to establish repeatability and error values and we found that it can reliably measure deflections of a top within +/- 0.001″ which is very acceptable.

There are several stages in the guitar construction process where it makes sense to perform deflection tests involving the soundboard. The first test is done during the selection of the tone wood material as part of the criteria in making sure that we start with an optimal piece of tonewood. The next is done before the braces are added to the soundboard in order to determine an optimal starting thickness for the top. The next is done during the final thicknessing and brace shaving step of soundboard tuning (which is what this blog article is about). The next one is done after the bridge is added to the soundboard. Finally, as the instrument approaches completion, the deflection caused by the tension of the strings is measured above and below the bridge and recorded.

Generally, the procedure we use for measuring and recording deflections is as follows.

Measuring the deflection from a weight placed at various points on a grid placed over the soundboard.

Before we start the deflection tests for the final thicknessing and brace carving stage of construction, we create a very thin paper template with a 1″ x 1″ grid on it which we place over the soundboard so that it is protected from scratches and dents. We use a very thin paper which we tested to confirm that it does not affect the deflection values. Initially we perform a full set of measurements before the bridge is attached to the soundboard.  Once the deflection measurements are taken, we normalize them based on a standard force value of 2 lbs. This is done so that data can be compared with values taken by other luthiers (as proposed by David Hurd).

Next we use a contouring program to map the deflection values for the entire soundboard.

Contour Map of Deflections produced by one of several free contouring applications available on the Internet.


This map is then reproduced on the full size Grid template.

Contour Map - Full Scale for Use in Tuning the Soundboard Braces

This sheet is initially used as a guide for where to take the deflection values and after the data is contoured, it is used as a guideline along with Chladni patterns in tuning the soundboard by adjusting the plate thickness and by adjusting the height and thickness of the braces.  This is an iterative process.  We carefully carve and adjust thicknesses and then take deflection values and perform Chladni tests again. 

Chladni Pattern of 2nd Mode for the German Spruce Soundboard

This pain staking process is repeated until we reach the pre-established guidelines we have worked out regarding the deflection pattern that we want in the final product. It is these guidelines that each luthier must develop and refine as part of their artistic contribution to this process. This allows us to achieve the ultimate balance between strength and the tonal quality we are wanting to achieve for each guitar. There is a lot of work and time involved in doing this but the payoff in a masterfully constructed hand crafted classical guitar is well worth it. I wanted to write this article so that our customers know how much care is taken to be sure the value of these guitars far exceeds the cost and that each Wood Ring guitar is truly an investment that is built to give them a lifetime of enjoyment.

 Links of Interest

Wood Ring Guitars – Unique Hand Crafted Guitars for Exceptional Musicians. Dallas, Fort Worth, Weatherford, Texas.

Left-Brain Lutherie by David Hurd – http://www.ukuleles.com/LBLBook/TOC.html

David Hurd’s Ukulele Website – http://www.ukuleles.com

Review of David Hurd’s Book – Left-Brain Lutherie

Quick Grid – Open Source Contouring Program

Of Science, Art, and Society Blog Entry on “Reading Tea Leaves to Predict the Future – Using Chladni Patterns to Create Extraordinary Classical Guitars”


Reading Tea Leaves to Predict the Future

Using Chladni Patterns to Create Extraordinary Classical Guitars

It may seem surprising to see this in a blog dedicated to Science and Art but it is true. My son Aaron and I regularly use tea leaves to predict the future! We are not seeking the winning numbers of the next Lotto Texas drawing, how Aaron’s romantic interests will play out, or whether it will rain next Sunday night (although that would be handy information). You see… instead of being a tasseographer, who seeks to predict the future by using superstition and folklore, Aaron is a luthier who uses science to make predictions about how his hand crafted classical guitars will sound. He is also a classical guitarist. He knows what he wants to create both visually and aurally. He knows how the guitar needs to feel in a guitarist’s hands. Yet even with all these artistic skills there is more to know when creating a high end classical guitar. Lutherie is tedious time consuming work and one mistake or bad judgment can cost you six weeks worth of time and hundreds of dollars in material costs. The bottom line is that Aaron wants to be able to know with some degree of certainty that as he carves, sands, scrapes, shapes, assembles and configures the components which eventually become a beautiful classical guitar, it will also be the best sounding instrument possible. This is where the tea leaves come in.

 How a Classical Guitar Works

Strings transfer vibrational energy to the soundboard.

The amplification of the vibration of the strings on an acoustic guitar is caused by a transfer of vibrational energy from the strings to the soundboard (the top plate to which the strings are attached).  From there it is transferred into the resonant cavity formed by the body of the guitar and into the air in front of and around the guitar. These components act very much like a loud speaker but are more complex because not only do they amplify the sound vibrations, they also add harmonic overtones which the listener interprets as the tonal quality of the guitar. The back of the guitar also contributes to the amplification to a lesser extent. All the components used in a guitar contribute to many other acoustical properties of the guitar like tone, sustain, harmonics, etc. It is the careful manipulation of several design parameters that allows Aaron to create the impressive beautiful sound of a Wood Ring guitar.

 Testing and More Testing

Testing is an essential part of the process of creating an outstanding classical guitar.

There are many processes and tests that we perform throughout the process of building each guitar that guides us toward the final great sounding product. Initially there are several tests that are used to evaluate each piece of wood being considered as a component of a guitar. Not only must the wood be visually appealing, it must have properties that are conducive to the production of the sound Aaron is looking for in his guitars. For instance, he is looking for pieces of wood that have a high strength to density ratio. This has to do with the need for the guitar to be light as possible in the hands of the player and yet strong and durable. A high strength to density ratio also allows stronger and longer lasting sound production with less energy input from the player.  He is also looking for wooden components where the internal damping of sound is minimal. This means that when energy is put into the guitar to make it vibrate, that the loss of energy to heat through internal friction is minimized.

 As construction proceeds, tests are done to guide us at each stage of construction toward the finished product. One test that we rely on is a process called Chladni testing of the soundboard. Of all the components of a classical guitar that the luthier creates, the soundboard arguably has the most influence on how the guitar sounds. The magic is in how the soundboard responds to vibrations. Sound vibrations transferred to the soundboard (either by guitar string or by loud speaker) occur as standing waves across the two dimensional surface. Since the vibrations are fast and the amplitude of the waves are very small, we must use an indirect way of seeing them. This is where the tea leaves used in conjunction with Chladni testing comes into play.

Graph showing the oscillating nature of a sound wave.

Great care is taken in the selection of the tonewood to be used as a soundboard as well as in the construction of the soundboard. We use Chladni testing to help us visualize and identify the resonant harmonic patterns that the soundboard favors. Every piece of wood used as a soundboard favors certain sound frequencies. The complete set of frequencies that a soundboard favors is like a voiceprint. It is a unique acoustic signature for each piece of wood used. It is the luthier’s job to evaluate and manipulate these signature frequencies to create a soundboard that brings out the full potential of the piece of wood that becomes a soundboard. It is the combination of these favored frequencies that experienced luthiers listen to when they tap on the wood to hear the wood’s tap tone. It is also the manipulation of these frequencies throughout the building process that helps the luthier create the optimum sounding guitar.

 Chladni Patterns

This Chladni testing process takes advantage of a phenomena called Chladni patterns. These patterns were discovered by a man named Ernst Chladni (pronounced Klahdnee) (1756-1827) who was a German physicist and musician. He has been called the “father of acoustics” because of his major contributions to the study of sound. He discovered that by drawing a violin bow across the edge of a thin plate of wood it would vibrate. When he placed some sand on the plate, he was able to create patterns by creating vibrations at different frequencies. Different patterns were created depending on the shape of the plate. See the images below.  The rectangular plate images of Chladni patterns were created by John Tyndall in 1869.  The circular plate images are from Chladni’s work on the subject.

Chladni patterns for rectangular and circular plates.

 The geometry of instruments like the guitar and violin generate patterns similar to both rectangular and circular plates. Different types of materials produce differing patterns as well. We have found that different species of woods can produce dramatically different patterns as well for a given shape. There are many variables that can affect the patterns during the testing process as well. Things like speaker location, how and where the plate is supported must be carefully controlled during testing so that repeatable and comparable results can be recorded and analyzed.

What is important to the luthier is that these patterns demonstrate visually how the sound waves travel through the plate. The places where the sand remains are the nodes of the wave pattern (where there is no vibration). The places where there is no sand are the anti-nodes of the wave pattern (where there is vibration).

Violin makers were some of the first luthiers to use this phenomena to fine tune their instruments. This process was documented in an article of Scientific American written by Carleen Hutchins a renowned violin maker who made huge contributions to the science of plate tuning of violins using Chladni patterns. This article described how these patterns can be used to guide the manipulation the top plate thickness to get an optimal sound.

Tests Performed in Crafting a Wood Ring Guitar

Our testing apparatus consists of a stand that we built for this specific purpose. It is based on a design described in the book called “Left-Brain Lutherie” by David C. Hurd, Ph.D.  David is a master at building Ukuleles. His book is a classic with regard to using the scientific method in the construction of stringed instruments. The guitar plate to be tested is placed on two tightly strung rubber bands one supporting the plate on each end. A speaker is placed under the guitar plate and is driven by a computer program which produces tones at any frequency the user desires. We place tea leaves on the plate to show the patterns. Sand, salt, glitter and saw dust have all been used to create Chladni patterns but we have found ground tea leaves to work very well for our purposes.  The full range of frequencies that a guitar can produce are scanned and the frequencies of the patterns are recorded along with the geometry of each pattern.

 The following is an image of some Chladni patterns we found for a rectangular piece of German Spruce that we will be featuring in a guitar Aaron is currently working with. This is a representative set of quality control tests that we perform on all pieces wood being considered as a soundboard for a Wood Ring guitar.  As you can see, the higher energy frequencies produce more complex patterns.

Chladni patterns recorded for a German Spruce wooden plate being considered as a soundboard.

 As the building process proceeds we again perform more Chladni pattern tests on each soundboard. We identify certain dominate patterns over the frequency range of the guitar that we can follow throughout the building process and watch how their absolute frequencies change as well as how their relative frequencies change. This information guides Aaron in the actions he needs to coax each guitar toward the sound he is seeking. The photos below show some of these patterns.

Chladni patterns of German Spruce soundboard before attachment to sides.

Chladni patterns of Western Red Cedar soundboard attached to guitar sides.

Thank You!

There are many luthiers that use the process of Chladni testing to create the outstanding guitars that are made around the world.  No one learns something this complicated without some help. Some of the luthiers that greatly influenced Aaron’s learning process are listed below. We wish to thank them for having the self confidence and generosity to share some of the knowledge they have spent so many years to develop so that others may stand on their shoulders to take lutherie to the next level.

Brian Burns – Brian’s website was influential in helping shape our testing program.  He has always been very encouraging in our correspondence with him.  Brian does consulting and also has some very nice lutherie tools for sale at a reasonable price.

Ervin Somogyi – A class act with regard to lutherie. Many of today’s luthiers have learned from Mr. Somogyi.

Luthiers of North Texas (LINT) – This is a group of luthiers who meet every two months in the Dallas – Fort Worth Area.  One member in particular, Derek Lambert, is a very good friend whose ideas, feedback and conversation in general are all greatly appreciated.

Classical Guitarists

There have been many fine classical guitarists in Texas that have been kind enough to play Aaron’s guitars and give him very candid and valuable feedback as to what they are looking for in the ideal guitar.  There are a couple that we would like to give special thanks to.

Fernand and Olga Vera – These are two dear friends that are amazing classical guitarists. Be sure and see them in concert or when they are playing at many of the local guitar festivals. Also don’t miss a chance to attend their annual workshop.

Mitch Weverka – Mitch heads up the Fort Worth Guitar Guild and has been a catalyst for promoting classical guitarists in the Fort Worth area. He also heads up the Fort Worth Guitar Guild. We are grateful to him for all the great feedback.

Interesting Links

Cymantics – A branch of science emerged in the 1960’s called Cymatics. It is the study of visible sound and vibration. This is a field of study which was named by Hans Jenny emphasizing the intersection between art and science in the study of unseen phenomena like standing waves in various types of media. 

TED Presentation About Cymantics by Evan Grant – A wonderful talk at the TED conference in July 2009 given by Evan Grant about Cymatics (the study of visible sound). It has some great demonstrations of Chladni patterns and how this study of the substance of things not seen is being applied in research around the globe. It is for instance being used to create a lexicon of Dolphin language and is also allowing artists to create wonderful art from different music sources from Beethoven to Pink Floyd.

How Guitars Work – Describes how classical and acoustic guitars work.

Wood Ring Guitars – Last but not least!  Don’t forget to visit the Wood Ring Guitars website.  Please contact Aaron Ringo to explore the possibility of having a custom hand crafted classical guitar made to your exact specifications.  We also have several very nice guitars in stock.  You will be amazed by the craftsmanship and sound.

     Copyright © 2011-2012 by Danny and Sandra Ringo.  All rights reserved.  Articles may not be reproduced without permission.