Friday, September 9, 2011

THE COLOR OF WOOD

There is a tendency among players to equate very dark colored wood with high quality. Here it is easy to be misled. In fact superb wood comes in a broad palette ranging from yellow through red and light to deep brown. The grain structure that denotes great wood can occur in different colors and some of the finest bows of the early makers Tourte, Eury and Pajeot are made of light brown or blond wood. Wood of poor quality also can be light or dark in color although there is a typical light orange hue to some of the lesser grades.

I have planed and given a coat of varnish to some rough bow blanks and then photographed them to show this variation. It’s better to see the actual wood but at least the photos give an idea. The first photo shows two high quality sticks from Espirito Santo state in Brazil showing the variation in color ranging from yellow to brown. The second photo shows an outstanding piece of Espirito Santo wood below a very poor grade of pernambuco wood that is too light and weak for a quality bow.

The issue of wood color is further complicated by the fact that pernambuco wood has often been treated to color the surface a dark reddish brown. Among other things, the natural dye in the wood can be set by applying nitric acid, by exposing the stick to ammonia fumes or sometimes both. This was a standard practice from the mid-nineteenth to mid twentieth century and bows were uniformly treated this way whether of high or low quality. For example, bows by fine bowmakers like Lamy, Vigneron and Sartory were treated with nitric acid. The effect was only on the surface and apparently any harm it did to the wood was insignificant. James Tubbs used a process that turned his sticks nearly black.

Here is a close-up picture of two nice bows by Alfred Lamy, a violin and an octagonal viola bow dating to around the turn of the century. These bows were treated with nitric acid and the wood was probably naturally lighter in color.

During the last three decades the new generation of bow makers has usually chosen to make bows without darkening the wood. This is in part because these younger makers were willing to invest in wood of exceptional beauty and this encouraged dealers and millers of the wood in Brazil to locate the best qualities. It is simply unnecessary to treat beautiful pernambuco and doing so risks losing some of the wood’s transparency and purity of color. But sunlight brings up the color in a nice way as the ultraviolet rays oxidize the surface. So we often put our bows in the sun for a few hours or even put them under an ultraviolet lamp in the winter.

Friday, September 2, 2011

EBAUCHAGE

Now a stick is being planed down prior to putting in the camber or curve. This stage is called the ebauchage or roughing out. During the cambering the stick will be one or two millimeters over the final dimensions allowing the stick’s taper or graduations to be subsequently matched or tuned to the stick’s curve. A substantial amount of time selecting the right pernambuco stick has already been invested in this bow. The violinist this bow is destined for wants to emphasize the rich warm sound his Vuillaume violin is capable of. He also plays with a Dominique Peccatte which brings out a beautiful chocolaty sound but in this case he would like something with a bit more power. The basic level of strength players currently want in a bow is fairly high given the scope of today’s repertoire but it is a mistake to over-react to this fact to the detriment of sound quality. Flexibility will promote warmth in the sound here so it will be more advantageous to make a bow that is almost too flexible than one that is more resistant than necessary.

For this bow I have gravitated in the choice to a lighter brown stick with a honey-brown striping, not too dense but very strong. The fresh shavings are light colored and darken in a few days in the air and light. The grain also has a certain pattern of perturbations that I feel will help accent the lower frequencies without cutting out the violin’s upper frequency incisiveness. The height and mass of the head and frog are important elements as well. Here I’m making a decision regarding the stick and how it is shaped based on experience and intuition. I’m confident I can make a bow that plays to my client’s taste, it’s the bow's sound potential that is my biggest challenge as a bow maker. Creating a sound signature in a bow is not something we can do with technical accuracy and the wood has a voice of it’s own.