A few months ago I was talking to Ervin Somogyi: a luthier whose guitars I love.  We were discussing various woods and generally geeking out.  Following a tip off, he had produced a guitar body out of Wenge (pronounced weng-ee).  Now I’ve made a few bass necks out of Wenge, and I know how hard it is.

The four neck stringers in this six string bass are Wenge. Truth is, it cost me a fortune in saw blades to cut them.  So I knew that the wood was very dense, but I had never considered building a guitar from it. This was because although Wenge has a dark, rich colour, it has almost no figure.

This guitar body he showed me was just an unfinished soundbox.  No neck attached.  I tapped the back and was astonished by the sound that emanated.  It is difficult to describe sounds in words, but this one was a clear, sustained, bell-like ring.  I don’t profess to predict the sound of a guitar just from tapping a piece of wood, but I do know what I am looking for.  A “lively” sound.  Proof that the wood has the ability to produce a note.  If it can do this, then the chances are that you will get a good guitar sound from it.  This guitar definitely had that – and some more besides.

In the case of Wenge, the properties of the wood that make it look boring are the very properties that make it sound great.  It has very tight, very straight grain, like the grain found in softwoods.  This uniformity means that it lacks the character, say, of a wild curly piece of maple. However, Wenge’s uniformity makes for a great-sounding guitar.

So I decided to experiment. I went out and bought the most perfectly quarter-sawn piece of Wenge I could find, joined it up to make a back plate and thicknessed it so that it would be extremely thin.  It’s a hard, stiff wood, so I can get it pretty thin; this should allow the back to move a lot.  This will add even more to the sound.

Now I’m thinking I’ll put some inlay in the back, to liven this guitar up a bit before it goes on sale.  I like my guitars to look a little exotic and, although I think this one will be perfect for the tone junkies out there, I also want to make it as striking as possible.

Here I’m gluing braces into the back.  I want this back to work as a single unit, hence the asterisk-style bracing.  As usual, I’ll be carving these braces to shape once they are on the guitar.  It’s so much easier to detect what influence your shaping is having on the guitar if they are attached to it when you work on them.

I’ll let you know how it sounds when it’s complete.  Obviously, for an independent view, you’ll have to come by and try it yourself.  The way the woods are sounding when I tap them, I think you’d probably better bring your cheque book if you do…

I built this bass in 2005. The koa top has a subtle flame and a rich, brown colour.

Koa (acacia koa) is a hardwood native to Hawai’i, and was used by ancient Hawai’ians to build dugout canoes. It is used frequently in making ukuleles, but is rare, due to logging. Most old growth wood now comes from stumps.

Old growth wood is more desireable then new growth and farmed wood, because of its figure. The reason why it looks so wild is because it has had a hard life. Growing from the side of a volcano in a rainforest with no protection from wind for 3,000 miles, it grows in strange ways; this causes a lot of the figure from within. If the tree is farmed and looked after, its grain will be more straight and true, and unlikely to be so beautiful.

I built this courting dulcimer in 2006. The back of this instrument shows how much variation can occur in one piece of wood. At one end, the flame is tight and even. After the waist, the flame suddenly gets much larger, and more irregular. This piece is typical of the most sought after pieces of koa, with its strong orange colouration and distinctive dark streaks.

The conservation of koa is a big concern. I am always careful to ensure that I only use FSC-accredited woods; when I build with koa, I use fallen or recycled wood, or stumpwood.

For me, the other tragedy of koa is that I’ve never heard a good-sounding koa acoustic. A customer of mine once told me about a Taylor built with koa that he rated, but most people feel that this wood is too bright. Brightness is something that you look for in a nylon stringed instrument, such as the ukulele. However, the challenge when building a steel stringed guitar is to try and build in some bass. This is because the nature of the instrument is that it will tend towards high end response.

This is my solution: koa binding! It works well against these cocobolo sides. I have also used it with rosewood, which provides another good contrast.

Apparently, mango wood has a very similar tone to koa, so I have braced the mango guitar I am building to draw out the bass response and counter the trebly predisposition of the back and sides. If this is successful – and my testing so far suggests that it will be – then maybe I’ll give koa another chance, and build an acoustic from it. A guitar with koa back and sides plus a great bass response is, to me, the ideal guitar.

Today I enjoyed another one of my favourite moments: finishing the box.  When you get the top and back glued to the sides, you can get an inkling of the guitar’s voice and tone.

With some judicious tapping, I was able to ascertain that this guitar has a good even response across its top, and that the back is vibrating well.  Then I blew compressed air over the soundhole, like blowing across the top of a milk bottle at a certain angle, so that the box began making a noise.  When this happened I felt the top vibrating, and I made douby sure that there were no inactive areas of the spruce top.

The back and sides of this guitar are made from a great piece of Mango.  When I found this piece of wood, the flame in the wood took my breath away. I also like the wide variety of colours accross this particular piece.  When it is finished, this guitar is going to be easy on the eye.

I have used a non-traditional bracing structure for this guitar, on both the top and back.  In this picture, the asterisk bracing on the back has been glued in, but not yet carved.  I have finished the inside of the guitar with shellac (French polish), to provide protection against the environment.