When did you make your first guitar?
When I was in secondary school (about 17 years old), I was fascinated by a semi-acoustic guitar I saw at a friend’s place. I dismantled an old plywood door at home and made a dreadful guitar painted red and reinforced with a tyre lever!
The second guitar I made from commercial plywood was even worse, and I put guitar making aside while I trained to be a Science teacher.
Was there a particular person you learnt your early skills from?
Not really. I read a lot of books and persevered intuitively from home with various materials and original designs.
Did you study the theory behind guitar making?
I was intrigued by the physics of soundboard vibration and sound generation while I was later studying post-graduate fluid physics at the ANU in Canberra. I used the facilities at the Physics Department to set up experiments and eventually published the results in music/acoustics journals in America and England.
Do you play an instrument yourself?
I played the guitar in a traditional band and used to accompany singers (like Eric Bogle) at Folk Clubs in Canberra. I don’t have any formal musical training, but I can play well enough to make people laugh.
What is meant by ‘new generation guitars’?
Traditionally, luthiers have crafted whole bodies of guitars, like violins, to vibrate optimally. ‘New generation guitars’ confine the sound generating vibration to a light, efficient soundboard with minimal vibration in the rest of the instrument. Many ‘new generation’ makers use carbon fibre to reinforce the soundboard for minimal weight and maximum efficiency.
How is the carbon fibre used?
Carbon fibre is by far the strongest material per unit weight in the known universe. It is the obvious choice for a maker seeking to minimise soundboard weight while retaining appropriate stiffness. There are several ways of using carbon fibre to achieve this. Most makers use soundboard braces reinforced with carbon fibre - some use actual carbon fibre on the underside of the soundboard itself.
Currently there are two main schools of ‘new generation’ making : the radial bracing with radial bars under the soundboard reinforced on the sides with carbon fibre; and the carbon fibre balsa lattice bracing of various geometries, where the balsa braces are capped above and below with carbon fibre.
Are there any disadvantages of using carbon fibre?
Yes, several! Firstly, it is very time consuming to fit carbon fibre lattices to soundboards. Secondly, profiling the lattice (shaping it from thick in the middle to thinner at the edges) is quite critical to the performance of the guitar and is not easy to master. Thirdly, fitting of the lattice must be done under low humidity and serious soundboard distortions can result from glueing under the wrong conditions. And fourthly, carbon fibre must be glued with just the right amount of epoxy resin in a very demanding operation.
How would you describe the trademark features of your guitars?
My soundboard design produces a powerful, sustained, lyrical sound across the playing range. Necks are reinforced with double-acting truss rods to control fingerboard relief accurately. Use of truss rods allows necks to be carved to a comfortable low (slim) profile.
Fingerboards are tapered on the bass side so that bridge saddles are level across the strings, facilitating good right hand action. It also keeps the twisting force on the bridge even across the strings, minimising soundboard distortion.
Bodies are made from figured blackwood, indian rosewood, and occasionally silky oak. Balancing the aesthetic of the instruments with figured woods on the headstock and rosette gives them a distinctive appearance without elaborate decoration.
Guitars are finished in durable lacquer, which is easily cleaned and easily repaired. Custom features like cutaway bodies, armrests, different string lengths and neck widths are welcomed.
The ‘guitar family’ is often associated with your name. What’s happening with it?
The Guitar Family has been a major part of my passion for instrument design and I have long hoped the guitar family would become incorporated into mainstream musical performance. After initial interest in the mid 80’s, from which the group ‘Guitar Trek’ emerged, the new possibilities for performance offered by the guitar family were not embraced by other musicians. However, since the year 2000, the development of guitar orchestras and ensembles has rekindled interest, and orders for trebles, baritones and bass guitars are on the increase.
What about steel string guitars? Do you make them?
I made about twenty steel string guitars in the 80’s, but found that established brand preferences dominated the steel string market. Also, the universal use of transducers in steel string guitars has diminished the importance of their acoustic qualities. Factory produced steel string guitars are essentially optimal in that genre, and sell for low prices relative to handmade instruments.
What is the price range of Caldersmith guitars?
I try to give the best possible sound quality per unit dollar i.e. keeping the workmanship high without spending untold hours on decoration. Currently, prices range between $AUS 4,000 for a treble (requinto) to around $AUS 8,500 for a classical bass, with standards and baritones somewhere in between. All guitars come with a quality case, and lined plywood cases are made to fit each 'guitar family' instrument. The 'Grange' models are currently priced at $AUS 4,000.
How long does it take to receive an ordered instrument?
Waiting time obviously varies depending on current orders and workload. Occasionally, we might have a guitar in stock, but usually there will be a waiting period of between two and six months.
Do your guitars sell overseas?
Yes. We have sold guitars to America, Germany and Italy. Transport risks are unavoidable and customs can be a headache for the buyer, so we prefer to send guitars as hand luggage with the buyer or a courier, as transport damage and 'humidity shock' are not infrequent.
What is meant by a lifetime guarantee?
Failure of any part of the guitar other than by accident or misuse will be repaired or replaced at no cost. I have replaced fingerboards and soundboards (on rare occasions!) and machine heads. I have corrected neck relief where warranted, promptly without question. I also routinely repair damaged finishes at very reasonable cost with minimum delay.
You also make instruments from the violin family. How does guitar making compare to violin making?
Good question! Violin making is highly refined and conservative - most violin makers can produce good instruments by following the recipes contained in a cornucopia of books and videos. By contrast, guitar making is a wide open field with the traditional methods being overtaken or challenged by radical new designs and technologies.
Do you think that making violins could inhibit your guitar making in some ways?
I always benefit from cross-fertilisation between two contrasting methods of making stringed instruments. I also gain by comparing the acoustic behaviour of the different instruments. I remain intrigued by the acoustic behaviour of violin and guitar bodies.
Are there any new developments you are currently working on?
I am continuing to develop the design for standard classicals - every instrument teaches me something new about guitar acoustics. The ‘guitar family project’ is still evolving, with refined designs for trebles, baritones and basses. I am now making Octave guitars in Grange and Carbon Fibre models. One of my next plans is to work towards construction of a guitar made solely from Australian tonewoods (as I have done with my ‘Aussiewood Violin’). I intend to try using King William Pine for the tops and something like brigalow for the fingerboards.