2018 Andrea Tacchi "Coclea Thucea - Fibonacci" CS/WE

This is Andrea Tacchi's flagship model, the "Coclea Thucea". It is a fusing together of two different design ideas that were developed independently. The first idea was born in 1989, when Tacchi publicly unveiled his "Coclea" model – named after the Latin word for the part of the inner ear that transforms sound vibrations into the psychological sensations of volume, timbre, and tone. It is based on geometric and mathematical concepts that Tacchi discovered in researching old stringed instruments starting with S. F. Sacconi's book "The Secrets of Stradivari" where Sacconi made sketches of violins and cellos that described the rules of dimensions and proportions that most influenced acoustic properties. Further, Tacchi explored the relationships found in the careful combining of circles and spheres to generate his plantilla (outline shape of the guitar) as well as the side-view shape with its unique back and soundboard doming. The second idea (the "Thucea" part of the story) came as a result of Tacchi having evaluated many original Torres guitars and noticing Torres' use of asymmetrical soundboards - center seam locations and number of pieces of wood used by Torres for his tops seems to have been done to ensure that the stiffest pieces of woods were normally found under the bridge area. This realization led Tacchi to develop a three-piece top made with two pieces of western red cedar at the extremities and a central piece of European spruce in the middle, named "Thucea" from the union of the Latin words "Thuja Plicata" (cedar) and "Picea Excelsa" (spruce). Tacchi’s idea was to work with woods of different densities (as Torres had done) to maximize the efficiency of sound transmission across the various sections of his soundboards, resulting in improved response and projection.

This guitar notably carries "Fibonacci" as part of its name which is primarily in reference to the rosette design which in itself is quite an artistic marvel. It has inlays of gold leaf in an expanding Fibonacci sequence, with the spaces in between filled with a Garcia-inspired checkered mosaics which are sized in "golden ratio" proportions generated from each of the preceding gold leaf measurements. The two inner rings are of brass, and at the upper extremities of the rosette (and in the tie block at the bridge) Tacchi has created a colorful collage, using inlay materials from other instruments as well as gold fragments, and even two pieces of semi-precious stone, in this instance - turquoise, which gives the guitar its unique fingerprint.

Notable qualities of this guitar are an easy emission of sound, a great variety of timbre, polyphonic clarity, increased volume, great playability and relaxed, comfortable string tension. Back and sides are made with wenge for the exterior and cypress for the interior (with gold leaf covered heel block!). Andrea has favored wenge for the back and sides of this model for over 20 years due to its assistance in production of a clean, focused quality of sound emanating from the box. No detail of this guitar has been overlooked - the bridge is made of padauk, with an ebony veneer (matching the head veneer), and in addition to the beautiful inlay already mentioned, the tie block is capped with horn which fades from dark to light at either end. Even the saddle itself is a composite of bone and carbon fiber to transmit vibration as efficiently as possible - Andrea sees this juncture of "string to body" in much the same delicate way as a needle on a record player. Fitted with Rodgers tuners and 20th fret. Overall a very sophisticated guitar, successfully achieving its intended aims, the primary of which is beauty of sound.

Orfeo Magazine article on Tacchi, Locatto and Frignani