Woods for the flamenco guitar top
In 1862 Antonio Torres (1817-1892) built a guitar with back and sides of papier-mâché, this guitar resides now in the Museu de la Musica in Barcelona. With this experiment Antonio Torres clearly proved that it was the top, and not the back and sides of the guitar that gave the flamenco guitar its responsiveness, its sustain and quality of each individual note.
Specifically for the spruce top tight-grained woods are required to have a lot of little cross silk grain patterns. These little grains, crossing the vertical long grains, are making some kind of bridges between the long vertical grains enabling the wood to respond in all its registers. Spruce is the most common used wood for making flamenco guitar tops. The best quality spruce is German spruce coming from the forests in Switzerland, Italy, Germany and the former Yugoslavia. German Spruce is quite stiff along and across the grains. Its high stiffness in combination with its light weight characteristics, create a high transmission of vibrational energy, making German spruce an excellent choice for the top of flamenco guitar. German spruce has the characteristics of a powerful, direct tone that keeps its clarity when playing strong rasgueados and alzapuas. Engelmann spruce from North America is less stiff resulting in a slightly lower velocity of sound and mainly used for steel string guitars because of its specific ability to absorb the harmonics of steel strings.
When German spruce became very expensive and hard to find, Jose Ramirez III (1922-1995) was the first luthier that introduced red cedar as a successful alternative for German Spruce. Due to the tight grain patterns, tonal responsiveness and stability of cedar, many famous luthiers started making guitars with cedar tops. The velocity of sound of cedar is higher compared to German spruce, cedar also has a higher overtone, but a lower fundamental tone. Spruce projects a brilliant, clear, strongly focused tone. From the first moment you play a flamenco guitar with a cedar top, you will feel the fuller, darker, more wooden, somehow sweeter, but less separated tone. However, this enchanting sound and responsiveness of Cedar does not improve with age. Spruce, on the contrary, opens up by age becoming increasingly responsive and mellow. Since cedar has a lower stiffness along the grain and spruce has the tendency to absorb humidity easily, it is very important that spruce is well-aged and properly dried until it can be used to make a flamenco guitar.