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New Projects:

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#222 - The latest projects all stem from things learned by building and then studying guitars #220 and #221 (aka The Jazzer). Both of these guitars had similar goals and succeeded in those goals but by different means and in different ways. The primary goal was to optimize the Bass Depth of the lowest notes by the means of expanding the active area of the soundboard, which on most classical guitars is limited to the lower bout. In addition, I started working with adjustable necks and on the Jazzer (#221) came up with a unique design that I intend to carry over to all the instruments I build from now on. It does require a cutaway and gives the player greater range than is found on any nylon string guitar I've ever seen or heard of.

 The results I achieved on these two guitars led me to design and build #222, which is only a platform for further experimentation of several different concepts. These concepts get the unromantic labels of 222-A, 222-B and so on. Don't expect me to try selling guitars with tops held on with bolts any time soon though.

The photo above (left) shows #222-A during a test session where various changes were made to the soundhole location and shape. Measurements were then taken to determine what changes occurred during the session. The top (the "A" part) and bridge become part of a testable module, as are sheets of wood taped onto the sides. The soundboard is clearly defined by the pattern of bolts. The bracing pattern originally used on the A version is shown on the right photo. Modifications were made to accommodate the 2 piece bridge design. This modular design allows a great deal of experimentation to take place in a minimal amount of time. By changing the modules, it is now possible to judge the effect of just the desired modifications while everything else about the instrument remains the same. My thanks to Argentine luthier Ricardo Louzao (Author of "La Guitarra Magica") for this idea. 

While I don't intend on building modular guitars for sale, I do have every intent of building future instruments based on the concepts proven in this test environment. Stay tuned...

 
  

Guitar #221 - I've played jazz standards and old show tunes on a classical guitar for several decades. It is my favorite musical style/instrument combination, but it has severe limitations due to the structure of the traditional Torres/Hauser design. Guitar #221 is directed towards removing those limitations with a highly arched fan braced top, severe cutaway body and dual sound holes strategically placed for maximum harmonic content of the main top and air resonance components. The neck is joined at the 14th fret, the cutaway is entirely clear to the 19th fret and the fretboard has a full 2 octave range on each string. This guitar is an attempt to retain a traditional Classical guitar tonal palette in a form more consistent with the expanded range of jazz arrangements. 

Nov 2011, A sneak peak at #211, no sound holes or back yet. The Fretboard is Texas Ebony, the top is Western Red cedar. Sides are cypress and the back is Indian Rosewood.

 

Guitar #220 (named "Wrinkle") is a departure from recent instruments. In fact it is the complete opposite. This will be a relatively heavy guitar with a removable and adjustable Indian Rosewood neck on a Macassar Ebony body. The neck shaft and fretboard are one and the same with a light weight Spanish Cedar peg head. The neck will have a negative angle placement and a compensated nut. I am debating using a top cutback on the treble side which would feature a tunable port. See THIS PAGE for more about #220. Finished.

 

 

Other Projects:

The ring bridge

Guitar #216 was a project that had the goal of trying some of the things a previous project had suggested. Bass response was the thing I was looking at and the small roundish bridge on the final version of #214 seemed to have a deepening effect on what was otherwise a series of very bright instruments. But 214 was not a standard type guitar, so I decided to apply a circular, "ring" bridge to a more or less standard design guitar.

 The bridge and peghead shown above are from#216. The bridge was carved from a single piece of Indian Rosewood. The strings wrap around brass pins, each pin has a radius roughly that of a fret. As shown, the action (string height) is determined by the number of times the string wraps around the pin. A variation of this uses angled grooves cut in the side of the pins to allow easier action adjustment. I don't know of anyone who has done this kind of bridge before, but I doubt I am the only one. This bridge weighs about 3 grams more than a standard style classical bridge. While it would not be difficult to make a standard slotted saddle for a bridge like this, I preferred to not weaken the structure of this one. The tie block has 12 holes for the string attachment. Most of the string tension is held by the multiple wraps on the pins, so there is not a lot of tension on the strings behind the pins.

The peghead is a design concept I've been working with where the head design is carved in layers of veneer, rather than outlined in the shape of the head as is customary. The main face veneer is a thick piece of Gabon Ebony with died veneers layered beneath it. The tuners are chrome plated Der Jung machines with rosewood buttons. The neck is red Alder with a Macassar Ebony fretboard. The back and sides are American Cherry and the top is Western Red cedar. All the woods are quarter sawn.

But the issue was sound and how a round bridge affected it. I did extensive testing on the top at every stage of construction. I took measurements from unbraced, braced, glued to sides, back attached, with a temporary standard bridge attached, with ring bridge attached, and strung up. Tap tone analysis of the assembled (no bridge) top showed a main top resonance (peak) of ~220Hz. This is pretty normal and often doesn't change much when a standard "stick" bridge is glued on. The reason being that the long rectangular bridge acts to re-enforce the monopole mode of vibration, which is usually where the main top resonance comes from. The ring bridge changes all that. Instead of re-enforcing the monopole, the ring bridge pushes a lower tripole mode and the result is a new peak (or in this case a series of peaks) around 143 and 159Hz. The peak at 220Hz is still there, but it is equaled or dominated by the 143/159 peak(s). So the top resonance becomes shared by multiple peaks of D3, D#3 and A3. The back has multiple peaks as well, A3 and B3, and the main air resonance for this guitar is F#2. Normally the air resonance is a bit higher, G#2, but this guitar's sides are 4 1/2 inches deep, causing the lower resonance.

So to clear away the techno-speak, this guitar has a very strong bass. It is strong and deep enough that tuning the sixth string to D2 is not an issue at all. In fact, the strong top resonance at D3 helps this to work well. However, It also has a thumper note at the open D string. Most people would refer to this as a wolf note, which is not accurate. Wolf notes are those which on a violin "howl". On a guitar the same basic cause (a close association with a wood or air resonance) results in a note which jumps out loudly initially but dies down quickly. To me it is like an audible thump, so I call it a thumper. The louder the note is plucked, the more pronounced the thump is. This is written after the guitar has been strung up for only one day, so time will tell if this becomes less of an issue with time and playing. The instrument has changed radically in the first 24 hours, from completely bass dominated, to much more balanced with a bright treble along with a deep bass. It is rare to have both in the same instrument, but I built the top to have both, and so far it is not disappointing. After it has been played in for a few weeks I'll post a sound file or two.

#214 relies on an internally supported tail piece to remove the string tension from the soundboard. This allowed me to build several soundboards without bracing. A removable back allowed me to add and change bracing to verify sound changes in very short amounts of time without even de-tuning the strings. Each variation was documented and recorded.

I am still debating whether to offer an instrument like this for sale. The final variation, with a Canadian Cyprus soundboard, Padauk back/sides, Red Alder neck and Macassar Ebony fretboard has very nice tone, decent volume and great sustain, but like all "no-tension" soundboard guitars has less of the dynamic response characteristics associated with highly stressed traditional guitars. This makes sense when you think about it.

#212 - The ultralight guitar

#213 - The tri-top guitar