In team sports like soccer there are individuals who “make” the play and others who “read” the play. A good balance of each is needed. In my opinion the same sort of balance is needed in a musical group.

As a maker my initial pursuit was in the direction of volume. Over time I concluded that volume for plucked instruments could be broken into 2 parts…..attack and sustain. Being more of a play “reader” my natural tendency was towards instruments with more sustain.

Experimenting with Dobros

The instrument I chose to experiment with is in a group of instruments from the 1930s known as the ” Resonators”.They certainly have a lot of volume and the one known as the dobro has long sustain. By experimenting with the dobro I was right in assuming a lot could be learnt or understood in a relatively short space of time. Once the “bed” of the dobro’s cone and spider is perfectly set up a change to a different cone spider combination takes less than 30 minutes. That definitely beats an average of 8 weeks to build an instrument. Because of this I took some extreme risks.

The cone and spider of the dobro is constructed with aircraft aluminium. I found the cone fairly easy to cast and proceeded to press out a number of carbon fibre cone combinations. I found no real improvements by using carbon except if it were placed on the rim allowing more freedom of movement and a huge improvement in bass response. I guess this is where I learnt what fundamental notes are……I am more than happy to explain this to any one who asks.

The spiders I built varied from carbon fibre reinforced timber{ebony} to solid carbon fibre. I also varied their weight and stiffness. I found the stiffer the better, and a solid carbon spider of no less than 60gm and preferably 80gms gave the best results for me. One of the spiders I built was 25gms and was placed in a mandolin. Upon hearing this instrument many people would say they thought it to be plugged in. Unfortunately the attack this instrument had was nearly as vicious as a banjo mandolin.

There is Spruce and Spruce and Spruce!

I need at this point to diverge with a small story……will get back to the Resonators…..By the way any sound board by definition is a resonator:

About 15 years ago I visited Steve Gilchrist. He is the most highly regarded F5 mandolin maker and he lived at that time less than a hundred kilometres from me. He was generous with advice with a big focus on fine tuning production processes. At that stage in my career design and materials were a bigger concern for me. One of my questions must have hit a raw nerve as the response was very emphatic. I cant remember it word for word but it went something like this:

Me: “I have been thinking of doing some experimental work designing sound boards with carbon fibre composites. What is your opinion on this?Steve:” Look, when it comes to sound boards there is Spruce and Spruce and Spruce. If you want to use something different use Spruce. Use Spruce!!”

I guess most individual’s response to such advice from a master would be to use Spruce. Since then I have acquired master grade samples of Sitka, Engelmann and Adirondack Spruce. The comparative mechanical tests that I did with this timber clearly showed to me that Spruce has excellent strength across the grain. My conclusion from this is that shock or string vibration would get out onto the sound board much more than other timbers.Spruce also has delightful tonal properties.

The reason why I have chosen not to use Spruce is that I simply prefer the “road least travelled”. It is for similar reasons why I chose to experiment with carbon fibre and its composites when building dobros.

Although the Resonators have some wonderful qualities their tone lacks the warmth and variety that timber can give. This was probably the main motivational reason behind why I chose to attempt designing timber Resonators. It has turned out to be a very long and interesting journey which I continue to travel…..more about that next week.

Regards Richard

Photo Credits:

Dobro: “1934 Dobro Style 37 Tenor Guitar” by Lowell Levinger. Original uploader was Kww at en.wikipedia – Transferred from en.wikipedia; transferred to Commons by User:Guitarpop using CommonsHelper.(Original text : http://www.vintageinstruments.com/photos/inst30/rwdobrotenrful.jpg). Licensed under CC BY-SA 3.0 via Wikimedia Commons.
Spruce: Dave Powell, USDA Forest Service, Bugwood.org – This image is Image Number 1359032 at Forestry Images, a source for forest health, natural resources and silviculture images operated by The Bugwood Network at the University of Georgia and the USDA Forest Service.

About the Luthiers Journey article series

Richard Morgan is a maker (luthier) from Australia and a member of theMandolinTuner community. From the moment that Richard joined theMandolinTuner we started exchanging e-mails and I was very happy to read about his work, especially as Richard mandolins (and mandolas, mandocellos, etc.) are truly innovative, featuring a unique sound-board design and lots of other innovations as well.

Soon, I start thinking of Richard as a friend of mine and I shared with him my vision of creating a section for luthiers within theMandolinTuner, something I believe would be very interesting for theMandolinTuner community. I am happy to say that Richard liked my idea and what you read now is a series of articles we have planned as the first step towards realizing this vision. I named this article series “A Luthiers Journey”.

So, enjoy Richard describing his journey as an instrument maker.

– Chris Rizos